STD-CUS-030 Type 298 User Guide for Circuit Breaker Cubicle

Issue Date: January 2014

Document Revision 2.3

Doc Ref: STD-CUS-030

Type298 Medium Voltage IEC Switchgear and Motor Control Centres

User Guide for Circuit Breaker Cubicle Incorporating PowlVac100

TM Circuit Breaker

Switchgear & Instrumentation

REVISION HISTORY

Revision Date Description Prepared

0.00 07/12/11 Original created from several existing IOMs and Technical

Data sheets.

Charlotte Pestell

1.0 18/12/11 Updated to incorporate comments from collaborative cross-

department review meeting

Charlotte Pestell

2.0 04/01/12 Updated to include required branding modifications Charlotte Pestell

2.1 11/01/12 Updated to incorporate comments following review Charlotte Pestell

2.2 2/1/13 Updated to reference STD/CUS/020 for lifting procedures Paul Dale

2.3 21/01/14 Updated Sect. 6.6./Added Sect 6.4 for 95kV BIL specific

requirements/ Updated Sect 6.3.4 for Vib & Seismic

Installation requirements.

Ignitius Milomo

The Design and Development Department is responsible for the data contained in this standard document.

The relevant departmental managers and team leaders are responsible for ensuring the correct use of this

data within their departments. The Engineering Manager is responsible for the correct use of the data within

the Contract Engineering department.

AUTHORISED BY

SD&D Manager_______________________ DATE _28nd

January 2014

P Dale

TYPE 298 PV100 Cubicle User Guide Doc Rev 2.3

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Contents

1 Getting Started ........................................................................................................... 7

1.1 About this User Guide ................................................................................................... 7 1.2 How to Use this User Guide .......................................................................................... 7 1.3 Application Notes .......................................................................................................... 8

2 Introduction ................................................................................................................. 9

2.1 Overview ....................................................................................................................... 9 2.2 Equipment ................................................................................................................... 10

3 Specifications ............................................................................................................11

3.1 Mechanical Specifications ........................................................................................... 11 3.1.1 Enclosure .........................................................................................................................11 3.1.2 Special Climatic Operating Conditions ............................................................................11 3.1.3 Weights and Dimensions .................................................................................................12

3.2 Electrical Specifications ............................................................................................... 13 3.2.1 Switchboard Specifications .............................................................................................13 3.2.2 Continuous Current Ratings ............................................................................................13 3.2.3 Internal Arc Classification ................................................................................................13

4 Circuit Breaker Cubicle ..............................................................................................14

4.1 Construction ................................................................................................................ 14 4.2 Withdrawable Circuit Breaker Compartment ................................................................ 14 4.3 Low Voltage Control Compartment .............................................................................. 14 4.4 VT Compartment ......................................................................................................... 15 4.5 Busbar Chamber ......................................................................................................... 15 4.6 Cable Chamber ........................................................................................................... 15

4.6.1 CT Specifications.............................................................................................................15 4.6.2 Cable Terminations .........................................................................................................15

5 Dispatch and Storage ................................................................................................16

5.1 Condition on Delivery .................................................................................................. 16 5.2 Packing ....................................................................................................................... 16 5.3 Export Packing ............................................................................................................ 16 5.4 Transport ..................................................................................................................... 16 5.5 Delivery and Intermediate Storage .............................................................................. 17

6 Installation .................................................................................................................18

6.1 Overview ..................................................................................................................... 18 6.2 Switchroom Requirements .......................................................................................... 18 6.3 Mounting ..................................................................................................................... 18

6.3.1 Foundation Frame or Unistrut .........................................................................................18 6.3.2 Switchroom Floor.............................................................................................................18 6.3.3 Raised Plinth ...................................................................................................................18 6.3.4 Installation requirements specific to Vibration and Seismic switchboard ........................18

6.4 Requirements specific to 95kV Basic Impulse Level (BIL) Switchboard ....................... 19 6.4.1 Busbar Chamber .............................................................................................................19 6.4.2 700 wide PV100 VCB Requirements ..............................................................................20 6.4.3 1000 wide PV

100 VCB Requirement ................................................................................21

6.4.4 Tier Requirements ...........................................................................................................22


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6.5 Mechanical Assembly .................................................................................................. 24 6.5.1 Site Requirements ...........................................................................................................24 6.5.2 Assembly of Cubicles ......................................................................................................24 6.5.3 Cubicle Fixing Bolts .........................................................................................................24

6.6 Assembly of Busbars ................................................................................................... 25 6.6.2 Assembly of Arc Ventilation Plenum ...............................................................................28

6.7 Torque Settings ........................................................................................................... 29 6.8 Electrical Connections ................................................................................................. 31

6.8.1 Connection of Mains Power and Control Cables ............................................................31 6.8.2 Earthing the Switchboard ................................................................................................31

6.9 Final Installation .......................................................................................................... 32 6.10 Extension Cubicles ...................................................................................................... 33

7 Pre-Commissioning ...................................................................................................34

7.1 Overview ..................................................................................................................... 34 7.2 Pre-connection Checks ............................................................................................... 34

7.2.1 General and Visual Checks .............................................................................................34 7.2.2 Control Wiring Completion Checks .................................................................................34 7.2.3 Low Ohm (Ducter) Tests (Minimum 50A) ........................................................................34 7.2.4 Primary Injection Tests ....................................................................................................34 7.2.5 Secondary Injection Tests ...............................................................................................34 7.2.6 Power Frequency Pressure (Flash) Tests .......................................................................35 7.2.7 Insulation Resistance Tests (Minimum 5kV) ...................................................................35 7.2.8 Electro-Mechanical and Functional Checks ....................................................................35 7.2.9 Protection Relays ............................................................................................................35 7.2.10 Final Checks ....................................................................................................................35

7.3 Energisation ................................................................................................................ 35 7.4 Standard Tools ............................................................................................................ 36 7.5 Special Tools ............................................................................................................... 36 7.6 Loose Items................................................................................................................. 36 7.7 Lubricants and Cleaning Agents .................................................................................. 36

8 Operation of the VCB Cubicle ....................................................................................37

8.1 Insertion and Withdrawal of the Circuit Breaker ........................................................... 37 8.1.1 Insertion ...........................................................................................................................37 8.1.2 Withdrawal .......................................................................................................................38

8.2 Test/Isolated Position .................................................................................................. 38 8.3 Interlocks ..................................................................................................................... 39

8.3.1 General Interlocks ...........................................................................................................39 8.3.2 Key Interlocks ..................................................................................................................40

8.4 Operating Mechanism ................................................................................................. 40 8.5 Earthing Switch ........................................................................................................... 41 8.6 Shutters ....................................................................................................................... 42

8.6.1 Maintenance Cradle ........................................................................................................43 8.7 Voltage Transformer .................................................................................................... 44

8.7.1 Insertion ...........................................................................................................................44 8.7.2 Withdrawal .......................................................................................................................44

8.8 Busbar Earthing Truck ................................................................................................. 45 8.8.1 Insertion ...........................................................................................................................45 8.8.2 Withdrawal .......................................................................................................................46 8.8.3 Operation .........................................................................................................................46


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9 Maintenance ..............................................................................................................47

9.1 Overview ..................................................................................................................... 47 9.2 Inspection and Servicing ............................................................................................. 47

9.2.1 Inspection ........................................................................................................................47 9.2.2 Servicing ..........................................................................................................................48

9.3 Repairs ........................................................................................................................ 49 9.3.1 Cubicles ...........................................................................................................................49 9.3.2 Replacement of VT Primary Fuses .................................................................................49

9.4 Electro-Mechanical Interlock Checks ........................................................................... 49 9.4.1 Circuit Breaker .................................................................................................................50 9.4.2 Circuit Earthing Switch ....................................................................................................50

Appendix 1: Abbreviations/Glossary of Terms ...................................................................51

Appendix 2: Related Documents ........................................................................................52

List of Figures

Figure 1 VCB Cubicle Layout 9 Figure 2 Busbar Barrier 19 Figure 3 Busbar Joint end Seals 19 Figure 4 Additional CT Support 20 Figure 5 V-Rubber Fitted to Busbar Chamber Cut-out 20 Figure 6 Shrink-wrapped contact Arms 20 Figure 7 Screw Caps on all Contact Mounting Bolts 21 Figure 8 Screw Caps on all Contact Mounting Bolts 21 Figure 9 Standard Inserts replaced by GP03 Blocks 22 Figure 10 700 mm Wide Tier Shutters 22 Figure 11 1000 mm Wide Shutters 23 Figure 12 Locating of Riser and Busbar Joint Plates into cover slots prior to strapping 25 Figure 13 Busbar Arrangement for Middle Tier (Side View) 26 Figure 14 Busbar Arrangement for End Tier (Plan View) 27 Figure 15 Earth Screen Connection 31 Figure 16 Circuit Breaker Operation 37 Figure 17 Interlock Box 39 Figure 18 Earthing Switch Operation 41 Figure 19 Shutters 42 Figure 20 Shutter Operating Mechanism 42 Figure 21 Maintenance Cradle 43 Figure 22 Voltage Transformer 44

List of Tables

Table 1 Mechanical Enclosure Specifications ......................................................................................................... 11 Table 2 Standard Cubicle Dimensions (mm) ........................................................................................................... 12 Table 3 Standard Weights of Loose Mechanical Items (kg) .................................................................................... 12 Table 4 Switchboard Electrical Specifications ......................................................................................................... 13 Table 5 Continuous Current Ratings (A) ................................................................................................................. 13 Table 6 CT Class ..................................................................................................................................................... 15 Table 7 Mounting requirements for Vibration and Seismic Switchboard ................................................................. 18


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1 Getting Started

IMPORTANT NOTICE � READ THIS FIRST

This User Guide does not purport to cover every detail of the installation and operation of the switchgear.

Requests for further guidance or information on this or any other product should be directed to Powell UK.

Our switchgear is manufactured in accordance with IEC standards. Powell UK cannot provide any

assurances that this product will comply with the wide variety of local codes, regulations or ordinances that

apply in different areas of the world.

1.1 About this User Guide This user guide provides user operation, installation and maintenance instructions for the TYPE 298

Switchgear.

The purpose of this user guide is to familiarize the user and maintenance personnel with the basic

capabilities of the switchgear. Only proven safe installation techniques are covered in this user guide.

This user guide was not prepared for inexperienced maintenance personnel. It is not intended to constitute a

training program or to provide sufficient background for personnel, not experienced with this type of electrical

system, to install the system described in this user guide.

The end user is responsible for ensuring that no persons should be authorised to install or carry out

maintenance work on the system without having read this user guide.

All rights reserved. Re-production of any part of this user guide in any form whatsoever without the written

permission of Powell UK is forbidden. Additional copies can be obtained from the After Sales Services Dept.

of Powell UK, Bradford, United Kingdom. The information contained within this user guide is confidential and

cannot be transferred to a third party without the written consent of Powell UK.

All efforts have been made to ensure the accuracy of the contents of this user guide. However should any

errors be detected, Powell UK would greatly appreciate being informed of them.

The above notwithstanding Powell UK can assume no responsibility for any errors in this user guide or the

consequences thereof.

The policy of Powell UK is one of progressive improvement in design, construction and operation. Systems

and equipment referred to in this user guide are subject to changes in keeping with this policy. The

manufacturer, therefore, reserves the right to make any changes without prior notice.

1.2 How to Use this User Guide This user guide is arranged and subdivided to provide useful information with a minimum of searching.

The key to easy reference is the Table of Contents. Every subject, in the Table of Contents, is listed with a

reference number and the page on which the item can be found. Each subject is numbered by Chapter,

Paragraph and Sub-paragraph, for example:

4.1.2. �4" - Chapter number.

�1" - Main paragraph topic.

�2" - Breakdown of Main paragraph topic.

The page number, along with the number of pages in this user guide, is located in the outside corner of each

page.

For convenience, all illustrations and tables are numbered in sequential order.


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Familiarity with the Table of Contents will facilitate locating particular information easily.

Personnel responsible for the system should review all of the Table of Contents for future reference and an

overall understanding of the user guide. Then read the user guide and study the illustrations thoroughly.

1.3 Application Notes MV Switchgear Warranty

Powell UK warrant the switchgear against defects in material or workmanship under normal use for a period of 18

months from the date of shipment from our premises or 12 months from the date the equipment is put into service,

whichever occurs first.

In the event of a failure arising during the warranty, Powell UK will undertake to repair or replace the switchgear at

our option, provided always that it is found to be defective. The warranty obligations of Powell UK will not extend to

defects caused by wrong or negligent operation, accident, overloading, unsuitable operating conditions, or by

failure of the End User to comply with any instruction given by Powell UK with regard to its operation or installation.

Powell UK is not liable under any circumstances for special, economic, financial, indirect or consequential damages

(including loss of profit, loss of use, loss of production, loss of contracts) or for expenses sustained as a result of

switchgear malfunction or incorrect application.

Safety at Work.

The voltages present in certain parts of the switchgear are capable of inflicting a severe electric shock and may be

lethal. It is the responsibility of the owner and / or the End User to ensure that the installation of the switchgear and

the way in which it is operated and maintained complies with the requirements of the Health and Safety at Work Act

in the United Kingdom, and with other applicable legislation and regulations and codes of practice in the UK or

elsewhere.

The manufacturer accepts no liability for any consequences resulting from inappropriate or incorrect installation of

the equipment.

Training

If additional training is required then contact Powell UK or their designated agent.

Type of operating environment

The intended operating environment is limited to being housed within an electrical switchroom or substation that is

suitable for protecting the equipment. Access to the switchroom and switchgear must be prevented except by

trained and authorised personnel.

General Operating Requirements

Users must have electrical experience and be able to interpret control circuit diagrams, electrical schematics and

general arrangement drawings.

Minimum age (years). Eighteen (18), or minimum permissible age required by End User�s national law.


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2 Introduction 2.1 Overview The Type 298 MV (Medium Voltage) switchgear is a modular construction of metal enclosures incorporating

various arrangements of incomer, feeder, bus tie and motor starter cubicles. The Incomer and bus tie cubicles are

fitted with a Circuit Breaker (CB) and the feeder cubicles can be fitted with either a circuit breaker or a Vacuum

Contactor (VC).

The cubicles that make up the switchboard are connected together via a Hard Drawn High Connectivity (HDHC)

copper bus bar system. HDHC copper risers are used to connect the equipment within each cubicle to the busbar

system.

Figure 1 VCB Cubicle Layout

As can be seen from the above side view, each VCB cubicle contains:

A withdrawable circuit breaker.

A Low Voltage (LV) control compartment containing terminals, control relays, MCBs etc.

A busbar chamber that allows the busbars to run into each cubicle for the risers to connect to.

A cable chamber for incoming and outgoing connections.

A voltage transformer in order to provide the control/metering supply (if required). There may not be a VT

in every CB cubicle supplied, but one or two per bus/switchboard. See contract drawings for details.


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2.2 Equipment The major components that are supplied as standard in the MV Incomer, Bus Tie and CB Feeder cubicles are as

follows:

Component Manufacturer Model No.

Circuit Breaker Powell UK PowlVac100

TM

Earthing Switch Contact Powell UK

Busbar Earthing Truck Powell UK

Voltage Transformer Transmag

This user guide discusses only the PowlVac100

TM breaker. The ABB VD4 and HD4 breakers are discussed in a

separate user guide.


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3 Specifications 3.1 Mechanical Specifications 3.1.1 Enclosure

IEC Publication Description Min Max Units

IEC 60470 High Voltage Alternating Current contactors and contactor-

based motor starters

IEC60529

Ingress Protection Rating:

IP 4X (standard enclosure)

IP 41 (enhanced enclosure)

IP 42 (enhanced enclosure)

IP 3X (between compartments)

IP 2X (inside the compartments with the door open)

IEC 62271

Maximum ambient temperature -20 +40 ° C

Maximum 24 hour average temperature -20 +35 ° C

Storage temperature -5 +55 ° C

Maximum 24 hour average storage temperature -5 +70 ° C

Average relative humidity over 24 hours 95 %

Average value of water vapour over 24 hours 2.2 kPa

Average relative humidity over 1 month 90 %

Average value of water vapour over 1 month 1.8 kPa

Maximum Site Altitude 1000 M

IEC 62271-1 High Voltage switchgear and controlgear

Common specifications


Alternating Current Circuit Breakers


Alternating Current disconnectors and earthing switches


AC metal-enclosed switchgear and controlgear

Table 1 Mechanical Enclosure Specifications

3.1.2 Special Climatic Operating Conditions For any operating conditions other than those described above, Powell UK must be contacted in advance.

Examples of these are as follows:

At site altitudes above 1000m the effects of the reduction in dielectric strength of the air on the insulation

level need to be taken into account.

Increased ambient temperatures must be compensated for in the design on the busbars and tee-off

conductors, otherwise the current carrying capacity will be limited. Heat dissipation can be assisted by

fitting additional ventilation facilities.

If the switchgear is to be operated in areas with high humidity and/or major rapid temperature fluctuations,

there is a risk of dew deposits. This situation can be exacerbated with low primary currents as internal

heating is not achieved. Anti-condensation heaters can be fitted in order to avoid premature insulation

degradation and corrosion.


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3.1.3 Weights and Dimensions

Description Current

Rating

Cubicle

Width

Cubicle

Height

Cubicle

Depth

Plenum

Height

Plenum

Depth

Overall

Switchboard

Height

40kA Switchboard <1600A 700mm 2204 1600/1990 428 1167 2630

50kA Switchboard <2000A 700mm 2204 1600/1990 428 1167 2803.5

50kA Switchboard <3150A 1000mm 2204 1600/1990 626 1167 2803.5

63kA Switchboard <4000A 1000mm 2404 2095 626 1270 3003.5

Table 2 Standard Cubicle Dimensions (mm)

Please note that extended depth is used when the switchboard is required to be top entry.

Description

Cubicle Width

700mm 1000mm 1000mm

(63kA)

40kA Circuit Breaker 245

50kA Circuit Breaker 245 310

63kA Circuit Breaker 415

Service Trolley 38 78 TBA

Shutter Operating Device 30 50 75

Voltage Transformer 100 100 100

Busbar Earth Truck 75

Earth Switch Operating Handle 1.5 1.5 1.5

Earth Switch Extension Handle 1.5

Racking Handle 0.5 0.5 0.5

Door Opening Hand Tool 0.25 0.25 0.25

CB Spring Charging Handle 0.25 0.25 0.25

Table 3 Standard Weights of Loose Mechanical Items (kg)


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3.2 Electrical Specifications The specifications detailed below are based on normal operating conditions as detailed in section 3.1 Mechanical

Specifications. If these conditions should differ (e.g. the site is at an altitude greater than 1000m or there is an

increased ambient temperature) then Powell UK should be consulted in advance as it may have an impact on the

specifications detailed below.

3.2.1 Switchboard Specifications

Description Switchboard Voltage Rating (kV)

3.6 7.2 12 13.8

Short-duration Power Frequency Withstand

Voltage (kV RMS) 10 20 28 38

Basic Impulse Insulation Level (BIL) 40 60 75 95

Rated Frequency (Hz) 50/60 50/60 50/60 50/60

Rated Busbar Current (A) ≤4000 ≤4000 ≤4000 ≤4000

Rated Peak Withstand Current (kA) ≤158 ≤158 ≤158 ≤158

Rated Short Circuit Breaking Current (kA) ≤63 ≤63 ≤63 ≤63

Rated Short Time (3sec) Current (kA) ≤63 ≤63 ≤63 ≤63

Auxiliary voltage (V) AC Voltages: 110/220

DC Voltages: 48/110/125/220

Table 4 Switchboard Electrical Specifications

3.2.2 Continuous Current Ratings

Description Available Ratings (A) Fault Rating

(kA)

700mm wide cubicle 630 1250 1600 2000 ≤50

1000mm wide cubicle 2500 3150 40001 ≤50

1000mm wide cubicle 3150 40001 ≤63

Table 5 Continuous Current Ratings (A)

3.2.3 Internal Arc Classification

The Internal Arc Classification for the MV298 Switchgear is tested in accordance with IEC 62271-200 Annex A

(Internal Fault � Method for testing the metal-enclosed switchgear and controlgear under conditions of arcing due

to an internal fault). The Internal Arc Classification (IAC) makes allowance for internal overpressure acting on

covers, doors, inspection windows, ventilation openings etc. It also takes into consideration the thermal effects of

the arc or its roots on the enclosure and of the ejected hot gases and glowing particles, but not damage to internal

partition and shutters not being accessible in normal operating conditions.

Please refer to the switchboard rating plate for specific details of the IAC of the switchboard supplied.

1 Forced Ventilation must be used for this rating.


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4 Circuit Breaker Cubicle 4.1 Construction The Type 298 MV switchgear consists of several segregated compartments:

Withdrawable Circuit Breaker Compartment

Low Voltage Control Compartment

VT Compartment

Busbar Chamber

These compartments are discussed in more detail in the following sections:

The main framework and internal faces of the switchboard are manufactured from Aluzinc. Doors and covers are

manufactured from mild steel and can be painted in any BS or RAL colour.

4.2 Withdrawable Circuit Breaker Compartment The circuit breaker compartment is fitted with guide rails in order to facilitate insertion and withdrawal of the

breaker. This is done with the use of a Service Trolley (see section 8.1 Insertion and Withdrawal of the Circuit

Breaker for further details).

At the back of the compartment are earthed metal shutters that are automatically operated by the shutter operating

mechanism such that no access can be gained to the primary disconnects when the breaker is in the

�Test/Isolated� position or completely removed from the cubicle. Please refer to Section 8.6 for further details.

Inside the compartment (mounted on the compartment top) is the control socket that the secondary disconnect

(multi-way control wiring plug) on the breaker connects into. This connection can only be made when the breaker

has been inserted into the compartment unless a special tool (CB test umbilical) is used.

When the breaker has been racked from the �In Service� position to the �Test/Isolated� position it is possible to

open the door and manually control the breaker using the Close/Trip buttons on the breaker itself. It is also

possible to perform a manual charge using the handle supplied. The Close/Trip and Charged/Discharged

indicators can be observed through the viewing window in the door when the door is closed.

Anti-condensation heaters (ACH) are also fitted in this compartment as required. These are controlled via a

thermostat which is located in the Low Voltage Control Compartment. Please note that at low loads, the heaters

should be permanently energised. Also, where end tiers draw little or no load, these heaters should also be

permanently energised.

4.3 Low Voltage Control Compartment This compartment, including the door, accommodates the auxiliary equipment of the switchgear panel. This

includes any protection relays and control relays etc. LV control wiring is situated within plastic trunking and

additional earthed metal trunking to the cubicle sides allows for bottom entry incoming LV connection direct to the

LV compartment. Bus wiring is routed between LV compartments through the cut-outs supplied.

A termination unit (TU) is also fitted into this compartment. This is used to distribute the RS485 cabling around the

switchboard to any intelligent control relays that may be fitted.

A thermostat is also fitted in this compartment. This is used to control the anti-condensation heaters located in the

circuit breaker compartment.


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4.4 VT Compartment This is situated below the Circuit Breaker compartment and can be equipped to accommodate a cradle mounted

voltage transformer. Guide rails are fitted in order to facilitate insertion and withdrawal of the VT.

At the back of the compartment is an earthed metal shutter that automatically operated by the shutter operating

mechanism such that no access can be gained to the primary disconnects when the VT is withdrawn.

There are no interlocks associated with the VT. The door is padlockable (a padlockable racking boss is available

on request), but after that it is possible to insert and withdraw the VT irrespective of the state of the breaker.

4.5 Busbar Chamber The busbars are laid in sections from tier to tier and are held in place by post insulators mounted on the steel

frame. Each busbar is constructed from 5mm HDHC copper bar insulted with an epoxy dip coating. Busbars are

used in single, double, triple or quadruple configuration depending on the current rating (refer to contract

documentation). The connections to the 5mm thick dropper busbars are made onto a special joint casting mounted

onto the post insulator and terminated into the busbar spout mouldings. All main circuit conductors are electro-

tinned or silvered at the joint faces of the bolted joints which are then covered by EPDM covers.

4.6 Cable Chamber This houses the Current Transformers (CTs), mechanically operated circuit earthing switch, primary cable

terminations and switchboard earth bar. Capacitive dividers and surge arrestors are also contained here if

supplied.

Neon indicators connected to the earth layer of the CT bushings may be fitted as an option to indicate that the

circuit side connections of a cubicle are energised.

Neon indicators for busbar live indication may be provided using busbar sleeving kits, or where possible, by

connecting to the bushing in a bus section cubicle.

Surge arrestors are fitted in this compartment where required. See contract document for details.

4.6.1 CT Specifications CTs are ring type with 600V insulation mounted onto fully fault rated CT bushings. Each bushing is constructed

with an earth shield between the HV and CT windings. Alternative cast resin insulated wound primary CTs may be

used in special circumstances. CTs are specified as follows:

CT Class Function Max.

Rating

Class 1/0.5/0.2 Metering ≤4000A

Class 5P/10P Protection ≤4000A

Class PX Differential & Residual Earth Fault ≤4000A

Table 6 CT Class

4.6.2 Cable Terminations Primary cable terminations are arranged to meet contract requirements with access from above or below. Gland

plates are provided at floor or unit top level with suitable accommodation for either single or multi-core cables as

required by the contract. Joints can be covered with polyurethane moulded covers (boots) if required. Please refer

to contract documentation for glanding details

Secondary cable terminations are made either top or bottom entry. Cables are terminated in the LV Compartment.

Bus wiring is routed directly between LV Compartments.

Internal earth bars and inter-panel earthing is mounted in the lower section of the cable chamber.


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5 Dispatch and Storage 5.1 Condition on Delivery The factory assembled switchgear cubicles are checked at the factory for compliance with the manufacturing order

and contract documentation.

All routine tests in accordance with all relevant specifications are conducted at the factory. Functional testing and

interlock sequence are checked with the final inspection.

Note: Horizontal busbars are not assembled within the equipment in the factory and are therefore not subjected to

an AC power frequency test on the assembly (this needs to be performed following installation. Please refer to

Section 7.2.6 Power Frequency Pressure (Flash) Tests. Each busbar is however, separately tested for integrity of

insulation by high voltage withstand testing. Busbars are supplied as loose material for completion at site during

installation.

5.2 Packing The switchgear sections are split and packed in accordance with the contract documentation. Standard packaging

consists of heavy duty welded seam polythene sheeting (minimum grade 500 gauge, micron value 125) applied to

each section. Packaging is often supplied in accordance with specific customer requirements.

Where the panel comprises more than one section, each piece will have an adhesive identification label.

All loose materials are detailed on a dispatch note and packed in a separate carton(s). See �Loose Material List�

supplied with the contract documentation for details.

For further details, please refer to the Packing/Unpacking Specification STD/CUS/008.

5.3 Export Packing The switchgear sections are split and packed in accordance with contract documentation. Standard domestic

packaging for export consists of a timber-framed, plywood clad case and all equipment is adequately wrapped. For

further details, please refer to the Export Packing Specification STD/CUS/007.

5.4 Transport The switchboard sections are normally transported as individual panels, or in small groups. Each panel is fitted

with two lifting channels mounted to the upper unit side frames. Please refer to contract drawings for details of the

shipping splits. For recommended methods of lifting, please refer to the Lifting Procedures document

STD/CUS/020.

Always transport switchgear panels upright and avoid sudden shock or jolting.


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5.5 Delivery and Intermediate Storage The responsibilities of the consignee when the switchgear arrives at the site include, but are not limited to the

following:

Check the consignment is complete and there is no obvious damage. In cases of doubt, the packaging

may be opened and then properly resealed when intermediate storage is necessary.

Precisely document any defect/transport damage and report these to the relevant authorities within two

weeks.

Storage is at the discretion of the consignee. Equipment packed according to customer specified documentation

shall be the responsibility of the customer.

Cubicles packed in our standard packing shall be stored as follows:

A dry, well ventilated and preferably heated storeroom in accordance with IEC 62271 (Please refer to Table

1 Mechanical Enclosure Specifications for details of ambient conditions).

Store switchgear cubicles in an upright position.

Do not stack switchgear cubicles.

Do not remove or damage the packaging.

Loosely cover unpacked switchgear cubicles with plastic film to prevent dirt and ingress

Cover all loose equipment with plastic film to prevent dirt ingress.

Sufficient air circulation must be maintained to prevent corrosion.


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6 Installation 6.1 Overview Once delivered to site, the switchgear can be assembled. This section details the switchroom requirements and

the mechanical and electrical connections that must be made. We recommend that any installation work is carried

out by Powell UK Site Services personnel. Please contact the Site Services team for further details regarding

installation personnel and activities.

6.2 Switchroom Requirements The minimum requirement for ceiling height in the switchroom is 3000mm for a standard IEC 62271 construction

switchboard. This will need to be higher for a 63kA switchboard. Please refer to Section 3.1.3 Weights and

Dimensions for further details.

6.3 Mounting It is recommended that the switchboard be mounted in one of the following ways:

6.3.1 Foundation Frame or Unistrut The switchgear and controlgear should be erected on a foundation frame or unistrut set into the switchroom floor or

onto a raised plinth. The completed foundation frame must be in accordance with:

Flatness ± 1mm per 1m

Straightness 1mm per 1m, but within 8mm over the entire switchboard length

Please refer to contract documentation for details of the foundation layout.

6.3.2 Switchroom Floor Switchboards with few lightweight cubicles can be fitted directly to the switchroom floor if the floor is level and has

sufficient load bearing capacity. If required, shims may be used to assist with alignment. The completed

switchroom floor must be in accordance with:

Flatness ± 1mm per 1m

Straightness 1mm per 1m, but within 8mm over the entire switchboard length

Please refer to contract documentation for details of the foundation layout.

6.3.3 Raised Plinth The switchboard can be supplied with a mounting plinth for mounting purposes. In order to facilitate the use of

earth trucks and service trolleys, any plinth must include a withdrawal area in front of the switchboard or the

switchroom floor must be screeded to the level of the plinth. Where required specific ramps can be supplied in

order to provide access between different floor levels.

6.3.4 Installation requirements specific to Vibration and Seismic switchboard The bolts, washers and load spreader bars required for assembling the cubicles are defined in the table below.

The bolt lengths may vary due to site specific installation requirements. Only the minimum length has been

specified in the table. These items are supplied as loose items with each cubicle.

Table 7 Mounting requirements for Vibration and Seismic Switchboard

Cubicles Description Qty Size Length

Any cubicle

to Plinth

Grade 12.9 Cap Screw 1/Mounting Position M12 ≥35mm

Load Spreader 1/Screw 09092P00014012

Locking Washer 1/Screw M12


Page 19 of 53

6.4 Requirements specific to 95kV Basic Impulse Level (BIL) Switchboard 6.4.1 Busbar Chamber

6.4.1.1 An additional GP03 plate is required. This is fitted to Busbar mounting plate (Ripple Plate) in order

to act as a barrier between the Riserbar of L1 and the horizontal Busbar of L3.GP03 Brackets are

provided and these must be secured using Nylon fasteners

6.4.1.2 All main horizontal Busbar are coated with an insulation of between 1.6mm & 2mm thick.

This reduces the gaps between adjacent bars and care must be taken when fitting the

Busbar Joint End Seals which are fitted all round the boot. Replacement Busbar Joint End

Seals which allow for the additional thickness of the insulation on the main Busbars are

required during site installation. Their references are shown below.

Figure 3 Busbar Joint end Seals

Joint End Seals or Joint Plates are fitted to Riser Bars on switchboards specified for Basic

Impulse Level (BIL) application. Detailed procedures for Assembly of Busbars joints are

discussed in Section 6.6.

GP03 Barrier between

L3 Busbar and L1

Riserbar, fitted to the

Ripple Plate

Figure 2 Busbar Barrier


Page 20 of 53

6.4.1.1 An additional CT support ring are placed on the CT bushings up against the original CT

support

6.4.1.2 V-rubber edging strip is fitted around the cut out for the interconnecting Busbars on each

tier. Ensure that these are secured.

6.4.2 700 wide PV100 VCB Requirements

6.4.2.1 The contact Arms in the Pole-Moulds have been insulated on the 2000A 50kA 700mm

Wide Vacuum Circuit Breaker and additional insulation shrink-wrapped and protrudes from

the existing Sleeves, see image below

6.4.2.2 All fixing screws used for mounting contact arms onto VI�s within a breaker have been

replaced with button head screws and covered using relevant size caps held in place by

Additional CT Support

added

V-rubber must be fitted

round the edge of the

Cut-out for the Busbar

Chamber

Heat Shrink-wrapped

Insulation over

Contact Arm

Figure 4 Additional CT Support

Figure 5 V-Rubber Fitted to Busbar Chamber Cut-out

Figure 6 Shrink-wrapped contact Arms


Page 21 of 53

non-conductive Loctite Sealant 5375. No gaps in insulation should be visible once all caps

and covers are fitted.

6.4.3 1000 wide PV100

VCB Requirement

6.4.3.1 Both upper and lower contact arms are insulated using powder coat insulation Button head

screws are covered using relevant size caps hold in place with non-conductive Loctite

Sealant 5375. Once all caps are fitted no gaps in insulation should be visible

6.4.3.2 All fixing screws used within fixing of contact arms onto the VI�s have been replaced with

button head screws

Screw Cover Cap

No visible gaps in

Insulation around

Nut Cap

Screw Cover Cap

No visible gaps in the

Insulation around Nut

Cap

Figure 7 Screw Caps on all Contact Mounting Bolts

Figure 8 Screw Caps on all Contact Mounting Bolts


Page 22 of 53

6.4.3.3 Plastic upper pole mould barrier have been replaced by GP03 barrier firmly fixed in place

using non-conductive Loctite Sealant 5375 in order to ensure no gaps are present down

sides or between barrier and upper contact arms

6.4.4 Tier Requirements

6.4.4.1 700 mm Wide Tier

The shutters including shutter mounting brackets are insulated. In addition, the upper shutter is fitted

with a polycarbonate sheet to the rear of the insulated shutter. Nut caps are also fitted to the Shutter

Mounting screws using Loctite 5375, see images below.

Plastic Inserts have

been replaced by

GP03 Blocks

Figure 9 Standard Inserts replaced by GP03 Blocks

Figure 10 700 mm Wide Tier Shutters


Page 23 of 53

6.4.4.2 1000 mm Wide Tier

The shutters including shutter mounting brackets are insulated. The upper shutter is fitted with an

additional polycarbonate plate to both the front and the rear. Nut caps are also fitted to the Shutter

Mounting screws using Loctite 5375, see images below.

Figure 11 1000 mm Wide Shutters


Page 24 of 53

6.5 Mechanical Assembly 6.5.1 Site Requirements Prior to installation at site, the switchroom must be completely finished, provided with lighting and site electricity

supply, lockable, dry and with facilities for ventilation. All the necessary preparations such as wall openings, ducts

etc. for routing of the power and control cables up to the switchboard must be complete.

6.5.2 Assembly of Cubicles Ensure the cubicles are moved to the prepared installation location in the correct order. Movement can be

accomplished using floor rollers (max. diameter 12mm) between the unit base plate and the site floor. It is

advisable to start assembly in the middle of the switchboard for larger installations i.e. 10 cubicles and above.

The assembly procedure is as follows:

Refer to the General Assembly (GA) drawing for cubicle locations.

Open rear doors and remove vertical partitions from the rear of the busbar chamber.

Fit the neoprene gasket (supplied) to the left hand side of each cubicle (front and top).

Align the cubicles onto the foundations one at a time. Ensure each section is correctly positioned relative

to the neighbouring cubicle. Alignment of the front face of the switchboard is essential.

Fit sections in the order shown on the GA drawing and bolt together

When the switchboard has been correctly assembled, fasten the panels to the foundation fixings.

6.5.3 Cubicle Fixing Bolts 6.5.3.1 Standard: The bolts required for assembling the cubicles are Grade 8.8 and the sizes and lengths

are as detailed in the table below. These are supplied as loose items with each cubicle.

Connecting Cubicles Description Qty Size Length

Any cubicle to any cubicle Front verticals 5 M8 35mm

VCB to VCB (any width) Rear verticals 10 M8 45mm

VCB (any width) to VCU Rear verticals 5 M8 45mm


Page 25 of 53

6.6 Assembly of Busbars The procedure for installing the busbars on a panel by panel basis is as follows:

Clean busbars with a dry, soft cloth and check for insulation damage. Remove all grease and adhesive dirt.

Slide joint covers to the base of the post insulators to provide access.

Fit busbars and packers as per contract specific assembly instructions, to the joint castings and riser

connections using fitting pins to provide support during assembly.

Fit correct length bolts, plain and spring washers into all fixing positions, removing fitting pins to allow bolt

fitting. Do not tighten.

Fully fit all busbars, packers and riser connections including joint plates to the switchboard prior to

tightening the fixing bolts to the specified torques. Please refer to Section 6.7 Torque Settings for details.

When all joint bolts are tight, slide joint boxes along the post insulators to final position.

Close joint boxes ensuring that joint plates correctly locate into the recess in the joint boxes.

Riser and Busbar Joint Plates must be fitted on all Switchboards. Figure 12 below shows a typical

preparation of the joint box arrangement prior to closing.

Joints at the ends of the busbar run are fitted with blank cover plates.

Fold outer covers into position and clip locating straps through holes in the fixed section and pull to lock in

position.

6.6.1.1 Busbar Fixing Bolts

All fixing bolts are 8.8 Grade, Metric Steel M10 Fixing Bolt Lengths (All dropper sizes)

Single Busbars

30mm

Double Busbars 40mm

Triple Busbars

Quadruple Busbars

50mm

60mm

For bolting together:

Quantity of bolts for 700 Wide Cubicle = 12

Quantity of bolts for 1000 Wide Cubicle = 24

Notes:

M10 plain and spring washer to be fitted under head of bolts into the joint casting.

M10 plain washer to be fitted under head of through bolls with M10 plain and spring washer under M10

full nut.

Figure 12 Locating of Riser and Busbar Joint Plates into cover slots prior to strapping

Riser Joint Plate

Busbar Joint Plate


Page 26 of 53

6.6.1.2 Busbar Arrangements for Middle Tiers

When the tier is located in the middle of a switchboard, the busbars are arranged as detailed in the diagram below:

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Page 27 of 53

6.6.1.3 Busbar Arrangements for End Tiers

When the tier is located at the end of a switchboard, the busbars are arranged as detailed in the diagram below:

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Page 28 of 53

6.6.2 Assembly of Arc Ventilation Plenum Arc ventilation chambers (plenums) are required in order to comply with the Internal Arc Classification element of

the IEC 62271 specification. Each cubicle has an individual assembly fitted into adjacent chambers. Plenums are

fitted onto cubicle top covers. The assembly procedure is as follows:

Fit neoprene gasket (supplied) to the plenum.

Mount plenums from the left hand end of the switchboard (viewed from the front).

Assemble the plenum. Note: on high current units the plenum fits over output thermal vents on the

cubicle roof.

Work along the length of the switchboard from the left hand end ensuring that the plenums locate.

Note: Bus section plenums sometimes include dividers. Please check contract documentation and fit if

required.

When all the plenums are fitted, fit covers to the ends.

Connect exhaust vent to the appropriate section. See contract documentation for details.

TYPE 298 PV100 Cubicle User Guide Doc Rev 2.2 Page 29 of 53

6.7 Torque Settings The information in contained in this section is as detailed in Torque Settings Technical Document STD/DOC/012.

Description Torque Settings (Nm)

Interconnections Copper/Copper M3 M4 M5 M6 M8 M10 M12 M16 M20 ISO M8.8 Grade Zinc Plated Bolt or Set-Screw - - - 9 21 34 54 109 203

Set-Screw into Brass Pillar - - - - 21 24 - - -

Interconnections Steel/Steel

Self Clinching Nuts (1) - 3.8 5.1 12.7 19.5 27 - - -

Self Clinching Studs (1) - 1.2 2.6 4.4 10.6 - - - -

Welded Nut - - - - - - 57 - -

Connections to Self-Clinching Studs (Previously PEM)

Flush Head Stud 0.74 1.7 3.5 5.9 14.2 - - - -

Connections to CT Bushings

Brass Bushings - - - - - 24 37 - -

Connection to ABB Surge Arrester (Aluminium)

ISO M8.8 Grade Zinc Plated Bolt or Set-Screw - - - - - - 28 - -

Connection to ABB NTGU12A1 Capacitive Dividers

ISO M8.8 Grade Zinc Plated Bolt or Set-Screw - - - - - - 31 76 -

Lifting Beams

Type 298 MV Switchgear - - - - 24 - - - -

Type 439 LV Switchgear - - - - - - 45 - - (1) Figures shown are 75% of manufacturers� torque-out data

(2) Torque Application to 3rd

Party products should be in line with the manufacturers� installation instructions


Description Torque Settings (Nm)

Type 439 LV Switchgear � Specific Torque Settings M3 M4 M5 M6 M8 M10 M12 M16 M20 Riser/Busbar Clamp Nut - - - - 30 - - - -

Busbar Chamber Brass Pillar Nut - - - - 10 - - - -

Riser Support Cap Head Screw and Nut - - - - 10 - - - -

Outgoing Connections - - - - 10 - - - -

Outgoing Socket Connections - - - - 15 - - - -

Type 298 MV Switchgear � Specific Torque Settings

Stand-off insulator to support plate - - - - - 14 - 76 150

Brass casting to stand-off insulator - - - - - 34 - 76 -

Copper Fixing into Stand-off Insulator - - - - - 24 - 76 150

Type 298 PV100 MV Switchgear � Specific Torque Settings

Connection from Pole Moulding to Upper Contact - - - - 15 24 - -

Upper Contact to Vacuum Interrupter Bottle - - - - - - 37 - -

Insulated Push rod to Vacuum Interrupter Bottle - - - - - - 37 - -

Guide Pin in the Cluster - - - - - - 24 - -

Push Rod (L1, L2, L3) Locknut - - - - - - - 76 -

Seismic Bolting Down of Type 298 MV Switchgear

ISO M8.8 Grade Zinc Plated Bolt or Set-Screw - - - - - - 82 - -

Seismic Bolting Down of Type 439 LV Switchgear

ISO M12.9 Grade Zinc Plated Cap Head Bolt - - - - - - 110 - -


6.8 Electrical Connections 6.8.1 Connection of Mains Power and Control Cables

Check the contract drawings for position, number, type and direction of access for power and control

cables.

Remove required gland plates, covers etc. and prepare for gland installation (glands may have been

ordered and supplied to contract).

Cut to length and strip power cables for attachment to gland.

Fit gland to cable and gland plate in accordance with gland manufacturer�s instructions.

Fit cable and gland plate assembly to the cubicle.

Prepare and secure the cable sealing ends in accordance with the manufacturer�s instructions.

Pass mains cable through CBCT (where one is fitted. Refer to contract documentation.). Ensure that

the earth screen from each core of the multi-core cable are connected together and passed back

through the CBCT and connected to the switchboard earth bar. See Figure 15 Earth Screen

Connection for details.

Connect the cable cores to the connection points on the end of the current transformer bushing,

ensuring that no undue stress is applied to the bushing.

Fit cable termination covers over the bushings, slot sub-cover in position and attach with rivet clips.

Connect cable earth.

Strip and fasten the control cables to the multi-core box gland plate with glands in accordance with

manufacturer�s instructions.

Fit cable and gland plate assembly to multi core box.

Terminate individual cores in compliance with the circuit diagram.

Make the control wiring connections to adjacent panels via bus wiring access holes in the instrument

chambers.

Figure 15 Earth Screen Connection

6.8.2 Earthing the Switchboard Ensure the cable earth is connected.

Connect the main earthing bar of the switchgear to the prepared connection links, panel by panel.

Make the earth connection to the foundation frame or the raised false floor.

Connect the earthing conductor from the ground electrode, preferably via a metering point, to the main

earthing bar of the switchboard.


6.9 Final Installation Check the paintwork of the switchgear for any damage, and touch up where necessary.

Check bolted connections; especially all those made during on-site assembly in the busbar and

earthing systems, and tighten to the specified torque where necessary.

Carefully clean the switchgear.

Remove all foreign bodies from the switchgear panels.

Properly refit all covers etc., removed during installation and connection.

Fit unit end covers to switchboard end panels. Please ensure that all insulation barriers and additional

barriers for extended depth cubicles are fitted.

Ensure all external holes into the chambers are blanked off with the correct plugs, screws, covers etc.

Check the isolating contacts and interlock mechanisms for smooth operation.

Remove protective caps etc. from circuit breakers (refer to relevant circuit breaker manuals).

Insert the withdrawable elements/power modules into the switchgear and control gear panels, ensuring

that each one is placed in the correct location, according to its rating, and is in compliance with the

general arrangement layout drawing.

Close and lock all front and rear doors.

Carry out full mechanical interlock checks. Refer to Section 9.4 Electro-Mechanical Interlock Checks

for further details.


6.10 Extension Cubicles Type 298 equipment is designed to allow extension cubicles to be fitted as required to either end of the

switchboard. The following procedure describes the work that needs to be carried out.

De-energise the busbars in full accordance with the site shutdown and permit to work requirements

Remove the panel end covers on the existing switchboard

If extending on the right hand end: Remove the busbar insulation barrier and replace with appropriate

half high or cut-out barrier.

If extending on the left hand end: Remove the busbar insulation barrier and dispose of as the

appropriate on is already fitted to the extension tier.

Move the extension cubicle(s) onto the prepared foundations in the order detailed on the revised

General Arrangement drawing. Movement can be accomplished using floor rollers (maximum diameter

12mm) between the cubicle base plate and the site floor.

Ensure each section is correctly positioned relative to the neighbouring cubicle. It is essential to ensure

correct alignment of the front face of the switchboard.

Bolt the cubicles together, noting that the insulation retaining strips are to be positioned between the

cubicles to provide partitioning between compartments.

Fasten the extension cubicle(s) to the foundation fixings.

Open the rear cable chamber door of the outer most cubicle on the originally installed Switchgear.

Remove the vertical bus bar chamber cover.

Remove the bolted end plate from within the bus bar chamber to expose the bus bar aperture into the

extension cubicle.

Fit the extension bus bars & busbar seals.

Re-fit the bolted end plate internally within the outer most bus bar chamber cubicle.

Replace all vertical bus bar chamber covers and close the rear cable chamber doors.

Re-fit the insulation barriers (if required) and end covers on the outer most cubicle ends.

Re-commission the bus bar system in accordance with Section 7 Pre-Commissioning of this manual.


7 Pre-Commissioning 7.1 Overview For the purpose of this manual, the term �Pre-Commissioning� refers to the work that is carried out to ensure that

the equipment operates as per the contract requirements. This includes post-installation testing and the set-up of

equipment such as protection relays in order that they functionally operate as intended by the electrical schematics.

More detailed commissioning work that concerns the detailed operation of the plant is not covered by this

document

It is recommended that all pre-commissioning work is carried out by Powell UK personnel and also that Powell UK

personnel assist with the detailed commissioning work. Please contact the Site Services team for further

information regarding both pre-commissioning and commissioning personnel and site activities.

7.2 Pre-connection Checks In preparation for pre-commissioning, the following work should be carried out prior to connection of the high-

voltage power supply:

7.2.1 General and Visual Checks Check the general condition of the switchgear for damage of any kind.

Remove all material residues, foreign bodies and tools from the switchgear.

Clean the switchgear, rubbing down insulating parts with a clean, soft, non-fraying dry cloth.

Remove greasy or adhesive dirt with a cloth dampened with a slightly alkaline household cleaner.

Wash off with clean water and dry carefully.

Perform a visual examination of the withdrawable elements, power modules, isolating contacts,

insulating parts etc.

For systems with a BIL of 95kV, check the correct fit and location of the additional parts required to

ensure compliance with the rated insulation level of switchgear panels, in line with the contract

documentation.

Visually check the connection of the main earthing bar to the station earthing conductor.

Check all busbar connections have been torqued to the correct level.

Check all busbar joints have been fitted with appropriate boots and shrouds.

7.2.2 Control Wiring Completion Checks Carry out a point-to-point wiring check of the tier interconnection wiring.

Ensure all connections are tight and that the cable marker is visible.

7.2.3 Low Ohm (Ducter) Tests (Minimum 50A) Perform a Low Ohm test through all closed and connected circuit breakers.

Perform a Low Ohm test through all closed and connected mechanically operated earth switches.

Perform a Low Ohm test through all busbars.

7.2.4 Primary Injection Tests Perform a primary injection test on the current transformers.

Perform a primary injection test on the voltage transformers.

These tests are optional. Primary injection testing is carried out on all voltage and current transformers in the

factory and it is at the client�s discretion whether these tests should be carried out again on site.

7.2.5 Secondary Injection Tests Perform a secondary injection test on all protection relays.

Perform a secondary injection test on all metering relays.

Note: Test voltage must match the system voltage


7.2.6 Power Frequency Pressure (Flash) Tests Perform flash test on all circuit breakers.

Perform flash test on all voltage transformers.

Perform flash test on all current transformers.

Perform flash test on switchboard.

7.2.7 Insulation Resistance Tests (Minimum 5kV) Perform insulation resistance test on all circuit breakers.

Perform insulation resistance test on all voltage transformers.

Perform insulation resistance test on switchboard.

7.2.8 Electro-Mechanical and Functional Checks Turn on the auxiliary and control voltage.

Carry out test operations of switching devices manually or by electrical control, and simultaneously

observe the relevant position indicators.

Check mechanical and electrical interlocks for effectiveness, without using force. Please refer to

Section 9.4 Electro-Mechanical Interlock Checks for further details.

Set the protective devices in the switchboard to the required values and check their function with test

equipment.

7.2.9 Protection Relays Configure protection settings in protection relays

Configure control and functional settings in protection relays

Configure communications settings in protection relays if required.

7.2.10 Final Checks Following completion of checks and tests, ensure that:

All test equipment and tools are removed from the switchroom or sub-station.

All temporary connections are removed and permanent connections are reinstated.

All covers removed to facilitate testing are reinstated.

All test results are documented on appropriate test sheets.

7.3 Energisation The following procedure describes the connection of the switchboard to the 3 phase mains power. Please note

that this activity is normally undertaken by the client with the assistance and supervision of our Site Services

Personnel. The following description serves only to provide an idea of what is required and a detailed procedure

provided by the client will take precedence over this.

Ensure that the circuit breakers in the switchboard are in the OFF position.

Remove any existing earthing and short circuiting connections in the critical switching area.

Energise the feed cables.

Connect the switchgear step-by-step, observing the signals and indicators.

Check the conductors are in phase as far as necessary when several incoming feeder cables and

switchgear sections are connected.

Carry out all measurements and check all functions dependent on the high-voltage power supply being

connected.

Pay careful attention to irregularities of any kind.


7.4 Standard Tools Standard tools that are supplied on each contract are as detailed below. Please refer to contract documentation for

any other special tools that may be supplied.

VCB Service Trolley

VCB Racking Handle

Door Handle/Rear Cover Handle

Earth Switch Handle

Busbar Earth Truck Extension Rod

VT Ramp

Manual Charging Handle

7.5 Special Tools Special tools that can be supplied if a requirement of the contract are detailed as below. Please refer to contract

documentation for details.

Maintenance Cradle

Test plugs & links

VCB test umbilical

Earth Truck Operating Handle

7.6 Loose Items Loose items that are supplied on each contract are as detailed below. Please refer to contract documentation for

any other loose items that may be supplied.

Cubicle Fixing Bolts

Busbar Fixing Bolts

Neoprene gasket

7.7 Lubricants and Cleaning Agents

Contact Lubricant - Contact Treatment Grease (For VT Contacts)

RS Components Ltd � Part No 503-335

Mobile Grease 28 (For Breaker Primary Contacts)

Mechanical Lubricant - Rocol MTS 1000 (For Tier)

RS Components Ltd � Part No. 691-397

Rheolube 368A (For Breaker)

Contact Cleaner - Electrical Cleaner


Insulation Cleaner - Electro Mech.


If RS Components Ltd products are not available locally, please contact Powell UK for an approved equivalent

supplier.


8 Operation of the VCB Cubicle 8.1 Insertion and Withdrawal of the Circuit Breaker

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Figure 16 Circuit Breaker Operation

8.1.1 Insertion The circuit breaker is inserted into the switchgear cubicle with the use of a service trolley (a service trolley is

provided for each cubicle width). The procedure for inserting the circuit breaker is as follows:

Unlock and open the compartment door.

Position the service trolley (with the breaker on) at the correct height facing the panel front. The height of

the trolley may need some adjustment and this can be done by winding the trolley adjusters up or down the

threaded bar as required.

Move the trolley up to the cubicle and ensure that it automatically latches to the cubicle such that it can�t be

moved away.

Operate the anti-rollout lever to release the breaker from the trolley.

Move the breaker forwards until it is fully inside the cubicle and the anti-rollout lever has latched onto the

anti-rollout bracket on the compartment mid pan.

The breaker is now inserted into the compartment and is in the �Test/Isolated� position.

Remove the breaker control wiring plug (secondary disconnect) from the storage position on the breaker

and connect it to the socket on the top of the compartment above the breaker.

Detach the trolley from the cubicle by moving the lever on the trolley (at the front and underneath the bench

top) to the right and pulling the trolley away.

Close and lock the compartment door. The breaker can now be racked into the �In Service� position using

the provided racking handle assuming all other interlocks will allow it.

Fit the racking handle to the hexagonal spigot of the racking mechanism through the access hole in the

compartment door.

Turn the handle clockwise until the stop is reached. It will take approximately 20 turns to achieve this.

NOTE: The circuit breaker must not be stopped at any position in the travel range between the �Isolated�

position and the �In Service� position.

Remove the racking handle.


8.1.2 Withdrawal The circuit breaker is removed from the switchgear cubicle with the use of a service trolley (a service trolley is

provided for each cubicle width). The procedure for withdrawal of the circuit breaker is as follows:

Ensure that the circuit breaker is open.


compartment door.

Turn the handle anti-clockwise until the stop is reached. It will take approximately 20 turns to achieve this.

NOTE: The circuit breaker must not be stopped at any position in the travel range between the �In Service�

position and the �Isolated� position.

Unlock and open the compartment door ensuring that the door retaining catch is disengaged before

opening.

Disconnect the breaker control wiring plug (secondary disconnect) from the socket on the top of the

compartment above the breaker and attach it to the storage position on the breaker.

Position the service trolley at the correct height facing the panel front. The height of the trolley may need

some adjustment and this can be done by winding the trolley adjusters up or down the threaded bar as

required.

Move the trolley up to the cubicle and ensure that it automatically latches to the cubicle such that it can�t be

moved away.

Operate the anti-rollout lever to release the breaker from the cubicle.

Move the breaker backwards until it is completely on the service trolley and the anti-rollout lever latches on

the trolley.



The breaker is now completely removed from the compartment.

8.2 Test/Isolated Position This is the position in which the breaker can be operated without actually energising the bus and is used for testing

and commissioning purposes. When in the �In Service� position, the breaker will operate and energise/de-energise

the bus.

When in this position it is possible to open the compartment door and manually open and close the breaker using

the Close/Trip button and to manually charge the breaker using the handle provided. A remote Open and Close (if

configured) will also operate the breaker in this position. For commissioning purposes a temporary supply will be

used to allow closure of the VCB to be tested.

This is the position from which it is also possible to completely remove the breaker from the cubicle.


8.3 Interlocks A series of mechanical and electro-mechanical interlocks are provided to prevent mal operation of the breaker that

could result in damage to the equipment or be dangerous to the operating personnel. These are as follows:

General Interlocks

Key Interlocks

8.3.1 General Interlocks These are a series of mechanical interlocks that are provided as standard to:

Ensure that the compartment door can only be opened when the breaker is in the �Test/Isolated Position�

or completely removed from the cubicle.

Prevent the breaker being racked into the �In Service� position with the door open.

Prevent the breaker from being operated when the door is open unless it has been racked into the

�Test/Isolated Position�.

Ensure that the breaker cannot be closed unless it is racked into either the �Test/Isolated� or �In Service�

position.

Ensure that the earthing switch cannot be closed when the breaker is in the �In Service� position.

There is also a series of mechanical interlocks that are provided via the Interlock Box (located under the VCB door)

and these are detailed below:

Figure 17 Interlock Box

Prevent breaker from being racked from the �Test/Isolated position to the �In Service� position.

Ensure that the breaker cannot be racked to the �In Service� position when the earthing switch is closed.

Prevent access to the earthing switch operating mechanism. This is done by blocking off the access hole

for the earth switch handle (see Figure 17 Interlock Box) using the padlock knob or key switch. Please

note that this is entirely operator-driven and is controlled only by turning the padlock knob or key switch

and padlocking it in the required position.

The following procedure details how to rack the breaker in and out of service.

Ensure the breaker is in the �Test/Isolated� position or is completely removed from the cubicle.

Full depress push rod.

Turn the key or wing knob (depending what has been ordered on the contract)

Remove key (if supplied).

It is now not possible to rack the breaker to the �In Service� Position.

Please refer to the following section for further details regarding key interlocks


8.3.2 Key Interlocks If required, a key interlocking system can be provided. This inhibits busbar earthing unless all incoming sources

are isolated. This section details some of the options in terms of operation but please refer to contract

documentation for exact details of the operation of this system.

A series of keys can be used to prevent actions being undertaken unless certain other conditions have first been

met. An example of this is busbar earthing. For example, in order to earth Bus A, Incomer A and the Bus Tie must

be racked out and the racking interlock applied. This ensures that the busbar earth switch cannot be racked onto a

live bus. This frees those 2 keys which then go onto an exchange box to release the busbar earth racking interlock

key.

Key Free Off

If a key free off system is selected, it means that access to the circuit earth switch is normally blocked. The key for

this is held elsewhere (usually upstream). When the upstream breaker has been isolated then the key can be

removed and placed in the interlock box. This in turn allows access to the key for the circuit earth switch and traps

the key from the upstream breaker, thus preventing it from being re-energised.

Key Free On

If a key free on system is selected, it means that the key which is normally trapped can only be removed when the

circuit earth switch is applied. Once applied, the key can then be removed and taken to a downstream breaker (as

detailed in the Key Free Off description above) or a transformer house.

8.4 Operating Mechanism The circuit breaker is fitted with a spring charging handle and open/close buttons on the front of the breaker.

These can only be operated with the door open, which means that the breaker must be in the �Test/Isolated�

position. A mechanical �push to trip� button can be fitted to the door if required to allow a local �Trip� command in

the �In Service� position.

Once the breaker is closed, the spring discharges and needs to be re-charged before another close operation can

be actioned. This is achieved via a motor charged spring charging mechanism which is fitted to the circuit breaker

to enable the spring to automatically recharge following a close operation. This can also be done manually using

the charging handle on the front of the breaker when the breaker is in the �Test/Isolated� position. Mechanical

indicators show �Spring Charged� or �Spring Discharged� status.


8.5 Earthing Switch The circuit earthing switch is located in the cable chamber has an independent manual closing mechanism which is

operated using the earth switch handle via the access hole in the interlock box on the front of the cubicle (refer to

Figure 17 Interlock Box). There is a user-operated mechanical interlock on the interlock box that blocks off the

access hole when the padlockable knob is turned. This prevents the earth switch handle from being inserted and

would be mainly used when the breaker is in the �Test/Isolated� position or completely removed from the cubicle.

An automatic mechanical interlock ensures that the earthing switch cannot be operated when the breaker is in the

�In Service� position.

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Figure 18 Earthing Switch Operation

The procedure for closing the earthing switch is as follows:

Ensure the breaker is in the �Test/Isolated� position or completely removed from the cubicle.

Ensure the door is closed.

Ensure the padlock has been removed from the padlockable knob and turned such that the access hole is

clear.

Insert earthing switch handle such that it engages with the hexagonal shaft of the switch itself.

Turn the handle anti-clockwise through approximately 180° until the stop is reached. Complete the

operation in one smooth action.

Observe the position of the switch via the mechanical position indicator. This should be red to indicate that

the switch is closed. Ensure that the position indicator does indicate that the switch is closed.

Remove the handle from the access hole.

The procedure for opening the earthing switch is as follows:

Observe the position of the switch via the mechanical position indicator. This should be red to indicate that

the switch is closed.

Turn the handle clockwise through approximately 180° until the stop is reached. Complete the operation in

one smooth action.

Observe the position of the switch via the mechanical position indicator. This should be yellow to indicate

that the switch is open.

Remove earthing switch handle.

Operate padlockable knob such that the access hole is blocked off and put padlock on.

The breaker is now available to be returned to the �In Service� position.

Please note that this applies to the earthing of this circuit only. For busbar earthing, please refer to Section 8.8

Busbar Earthing Truck.


8.6 Shutters

Figure 19 Shutters

Shutters are provided to shroud the primary contacts when the breaker is in the �Test/Isolated� position or

completely removed from the cubicle. These shutters are automatically operated via the shutter operating

mechanism as the breaker is racked in and out. The details of this are as follows:

As the breaker is racked from the �Test/Isolated� position to the �In Service� position, the shutter drive

bracket on the circuit breaker (see Figure 16 Circuit Breaker Operation) makes contact with the shutter

operating mechanism, which in turn opens the shutters and allows the breaker to be connected to the

busbars.

As the breaker is racked from the �In Service� position to the �Test/Isolated� position, the shutters close

thus preventing access to the primary contacts.

With the breaker completely removed from the cubicle it is possible to padlock the shutter operating

mechanism to prevent accidental operation of the shutters during maintenance of the circuit breaker

compartment. Please note that the bottom padlock position is used to lock the top shutter and the top

padlock position is used to lock the bottom shutter.

Figure 20 Shutter Operating Mechanism

Note:

The shutter colours (as depicted in Figure 19 Shutters) relate to a bus tie. The bottom shutter on an

incomer/feeder is yellow and where a tier is a designated busbar earthing tier, there is only a single red shutter.


8.6.1 Maintenance Cradle

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Figure 21 Maintenance Cradle

Where access to the spout bushings is required for maintenance purposes, it is possible to operate the shutter

operating mechanism via a maintenance cradle. This is inserted into the compartment in the same way as the

circuit breaker, but because it is only a base frame construction, access can still be gained to the compartment and

thus the shutters and primary contacts.

The maintenance cradle can operate only one shutter at a time and the height of the shutter drive bracket on the

cradle determines which shutter is opened. This height is altered by turning the opening bracket round prior to

inserting it into the compartment.

When the maintenance work is complete and the maintenance cradle is removed and the compartment is ready for

normal use with a circuit breaker.


8.7 Voltage Transformer

Figure 22 Voltage Transformer

The Voltage Transformer (VT) is a 3 phase, cradle mounted, cast resin withdrawable element.

8.7.1 Insertion The procedure for inserting the VT into the compartment is as follows:


Wheel the VT into the compartment using the ramp provided, such that it connects in the �Isolated�

position.

Close and lock the compartment door


compartment door.


NOTE: The VT must not be stopped at any position in the travel range between the �Isolated� position and

the �In Service� position.


The VT is now in the �In Service� position and is connected to the system.

8.7.2 Withdrawal The procedure for withdrawing the VT from the compartment is as follows:


compartment door.


NOTE: The VT must not be stopped at any position in the travel range between the �In Service� position

and the �Isolated� position.

The VT is now in the �Isolated� position and ready to be removed from the compartment if required.



Wheel the VT from the compartment using the ramp provided.

Close and lock the compartment door.


8.8 Busbar Earthing Truck The busbar earthing truck is 3 phase, cradle mounted and withdrawable. These trucks can be accommodated in

the incomer and bus tie sections in place of the circuit breakers or in designated earthing cubicles.

8.8.1 Insertion The busbar earthing truck is inserted into the switchgear cubicle with the use of a service trolley (a service trolley is

provided for each cubicle width). The procedure for inserting the earthing truck into the compartment is as follows:

If an incomer or bus section is to be used, ensure the breaker has been removed. (See Section 8.1

Insertion and Withdrawal of the Circuit Breaker for further details).

Unlock and open the compartment door

Position the service trolley (with the earth truck on) at the correct height facing the panel front. The height

of the trolley may need some adjustment and this can be done by winding the trolley adjusters up or down

the threaded bar as required.

Move the service trolley up to the cubicle and ensure that it automatically latches to the cubicle such that it

can�t be moved away.

Operate the anti-rollout lever to release the earth truck from the trolley.

Move the earth truck forwards until it is fully inside the cubicle and the anti-rollout lever has latched onto the


The earth truck is now inserted into the compartment and is in the �Isolated� position.



Close and lock the compartment door.


compartment door.


NOTE: The earth switch must not be stopped at any position in the travel range between the �Isolated�

position and the �In Service� position.



8.8.2 Withdrawal The earth switch is removed from the switchgear cubicle with the use of a busbar earthing truck. The procedure for

withdrawal the earth switch is as follows:


compartment door.


NOTE: The earth switch must not be stopped at any position in the travel range between the �In Service�

position and the �Isolated� position.

Open the door.

Position the earthing truck at the correct height facing the panel front. The height of the trolley may need

some adjustment and this can be done by winding the trolley adjusters up or down the threaded bar as

required.

Move the truck up to the cubicle and ensure that it automatically latches to the cubicle such that it can�t be

moved away.

Operate the anti-rollout lever to release the earth truck from the trolley.

Move the earth truck forwards until it is fully inside the cubicle and the anti-rollout lever has latched onto the


Detach the truck from the cubicle by moving the lever on the truck (at the front and underneath the bench

top) to the right and pulling the truck away.

The earth switch is now completely removed from the compartment and the circuit breaker can be inserted.

(See Section 8.1 Insertion and Withdrawal of the Circuit Breaker for further details).

8.8.3 Operation If the busbar earthing truck is used in a circuit breaker cubicle, ensure that the circuit breaker has been

removed from the cubicle.

Insert the earth truck into the cubicle.

Close and lock the cubicle door.

Ensure that all interlocks have been safely removed and rack earth truck into the �In Service� position.

Take the handle used for operating the circuit earthing switch and fit the extension handle provided.

Turn wing knob on the circuit breaker door to open the earthing switch handle access hole.

Insert earthing switch handle such that it engages with the hexagonal shaft of the switch itself.

Turn the handle clockwise through approximately 180° until the stop is reached in order to closed the

switch.

Observe the position of the switch via the mechanical position indicator through the window in the door.

This should be red to indicate that the switch is closed.

To open the earth switch, turn the handle anti- clockwise through approximately 180° until the stop is

reached.

Remove the operating handle.

Turn wing knob to close access hole.


9 Maintenance 9.1 Overview Maintenance serves to preserve trouble-free operation and achieve the longest possible working life of the

switchgear. It is recommended that routine maintenance be carried out at regular intervals in order to reduce the

number of repairs and the unplanned shutdown time. The Planned Preventative Maintenance (PPM) intervals are

as follows and comprise the activities detailed below:

1. 6 month period � Inspection

2. 12 month period � Inspection and service

3. 2-5 year period � Inspection, service and full test

4. Repairs to be carried out as required during inspection and servicing.

Maintenance work may only be performed by trained personnel familiar with the characteristics of the individual

switchgear, in accordance with all relevant safety regulations and with other overriding instructions. It is

recommended that Powell UK service personnel carry out any servicing and repair work. Please contact the Site

Services team for further information regarding maintenance personnel and activities.

9.2 Inspection and Servicing The inspection and servicing intervals for some of the equipment/components (e.g. parts subject to wear) are

determined by fixed criteria such as switching frequency, length of service and number of short-circuit breaking

operations. For other parts, the length of the intervals may vary, depending on the different modes of operation, the

degree of loading, and also environmental influences (including humidity, extreme cold, pollution and aggressive

air).

In addition to this document, it may be necessary to refer to the operating instructions for the individual

components, such as:

Circuit Breaker

Earthing Switch

Voltage Transformer

Low Voltage Equipment

9.2.1 Inspection The inspection should include but not be limited to the following:

Isolate the area where work is to be performed in accordance with the relevant safety regulations, to

IEC/HSE and other authorities, and secure it against reconnection.

Check the installation for abnormalities of any kind, dirt and the effects of other environmental

influences.

Check the function of the switching devices and the controls, interlocks, protection, annunciation and

other devices.

Check the surface condition of the isolating contact system (the shutters can be opened and secured

with the shutter operating mechanism for visual examination of the fixed contacts with the breaker

removed). If the silver plating on the contact parts is worn to such an extent that the copper conductor

material below becomes visible, or if their surfaces are corroded, or shown signs of other damage, or

overheating (discoloured surface), contact the Site Services Team.

Where thermographic windows are fitted, check busbar connections for hotspots. If any are found,

contact the Site Services Team.

Check all switchgear accessories and the auxiliary equipment (e.g. storage batteries, operating

handles, service trolleys, shutter operating devices etc.).

Check there is no external discharge on the surfaces of equipment at operating voltage. This can be

detected by characteristic noises, a clearly perceptible smell of ozone, or visible glowing in the dark.


9.2.2 Servicing Basic servicing activities, and those which may be found necessary during inspections, include the following:

Carefully clean the unit (in particular the insulating material surfaces) when they are found to be dirty as

contamination may be caused by salt, mould formations, insects or conductive materials in conjunction

with frequent condensation when the switchgear is operated in a tropical climate. Remove dry dust

deposits which do not adhere strongly using a soft dry cloth. Remove more strongly adhering, e.g.

sticky/greasy dirt, with a cloth dampened in a slightly alkaline household cleaner. Wash off with clear

water and dry carefully.

Use halogen-free cleaner Electro Mech (268-2115) for insulating material components and for major

contamination. Do not use 1.1.1-trichloroethane, trichloroethylene or carbon tetrachloride, etc.!

Should there be evidence of external discharges occurring as a result of condensation, clean the area

thoroughly as above and apply a thin silicone film on the surface concerned as a temporary remedy.

Please contact the Site Services team to discuss a permanent solution to this problem.

Check that the bolt connections at the contact points in the busbar system and the earth connections

are tight. For the torque settings refer to Section 6.7 Torque Settings.

Thoroughly clean all contacts using electrical cleaner (203-0750) and re-grease using contact treatment

grease (505-335). Ensure the isolating contact system functions correctly.

Re-grease the mechanism of the breaker insertion system as necessary, or, when lubrication is

inadequate or missing, thoroughly clean the areas concerned and re-grease with Rocol MTS 1000 (691-

397)

Top up the grease on all sliding and bearing surfaces in the panels. For example; the shutters, the

interlock and guide systems, the spindle mechanism and the circuit breaker wheels. Where necessary

thoroughly clean and re-grease with Rocol MTS 1000 (691-397).

Observe the maintenance instructions in the manuals for the individual circuit breaker and switch

elements.

Note:

In installation areas prone to problems caused by airborne silicone agents, insulation components can be cleaned

and sealed using a mixture of one part white spirit to one part transformer oil sparingly applied to insulation

surfaces.


9.3 Repairs This section describes the minimum repairs that are likely to be carried out.

9.3.1 Cubicles Repair work on cubicles must be carried out immediately after a defect has been discovered. The following

procedures describe how to repair:

1) Painted Surfaces

Lightly grind the surrounding paint coat and carefully degrease the entire area. Then immediately apply an anti-

rust primer and, after an appropriate hardening time, apply the top coat. The total dry film thickness should be

approximately 60 microns. Only use suitable and compatible paint products.

The top coat should be in the relevant contract specific colour.

2) Coated Steel Surfaces

Lightly grind the surrounding coated area and carefully degrease the entire area. Immediately apply a coat of

aerosol zinc plate.

3) Mechanical Plated Parts

Remove any rust deposits from zinc plated or tuftrided mechanism parts with a wire brush. Clean loose parts with a

clean dry cloth and degrease where appropriate. Re-grease linkages and bare surfaces with Rocol MTS 1000

(691-397).

9.3.2 Replacement of VT Primary Fuses

The primary fuses are located within the contact arms and the procedure for replacing them is as follows:

Unlock and open VT compartment door.

Withdraw the VT from the compartment. (See Section 8.7 Voltage Transformer for further details.)

Remove the contact shroud and moving contact revealing the primary fuse.

Pull the primary fuse from the contact arm and remove the rubber centralisation bung.

Fit rubber centralisation bung to the new fuse, replace the primary fuse and refit the contact shroud

assembly ensuring that the contacts are horizontal and that the fixing screws are tight.

The VT may be fitted with either secondary fuses or MCBs depending upon contract requirements.

These will be located in the LV compartment. Reset or replace as necessary.

Note: For further protection of the system, additional secondary fuses or MCB s may be fitted within the LV

chamber. Check before re-energising the VT.

9.4 Electro-Mechanical Interlock Checks Before the cubicle can be put back into service, the interlock functions must be tested as follows:


9.4.1 Circuit Breaker It should only be possible to rack the breaker from the �Test/Isolated� position to the �In Service� position when the

circuit breaker is open and the earthing switch is open. This is tested as follows:

With the circuit breaker closed, rack the breaker towards the �In Service� position. This should be

blocked after half a clockwise turn of the handle.

With the earthing switch closed, rack the breaker towards the �In Service� position. This should be

blocked after only two clockwise turns of the handle.

It should only be possible to rack the breaker from the �In Service� position to the �Test/Isolated� position with the

circuit breaker open. This is tested as follows:

With the circuit breaker closed, withdraw the breaker. This should be blocked after half an anti-

clockwise turn of the handle.

It should only be possible to close the circuit breaker when in the �Test/Isolated� position or in the �In Service�

position. This is tested as follows:

Attempt to close the breaker in between the two positions. This should not be possible.

Ensure that it is possible to open and close the breaker in the �Test/Isolated� position and the �In

Service� position.

When the breaker is closed in either the �In Service� or �Test/Isolated position and the control voltage has failed; it

should only be possible to trip the circuit breaker manually. This is tested as follows:

Attempt to close the breaker. This should not be possible.

Attempt to trip the breaker. The breaker should open.

9.4.2 Circuit Earthing Switch Operation of the circuit earthing switch must only be possible when the circuit breaker is in the �Test/Isolated�

position or completely removed from the cubicle (subject to any additional electromagnetic solenoid interlocks fitted

to meet contract requirements). Check these conditions as follows:

When the circuit breaker is in the �Test/Isolated� position and is being racked to the �In Service�

position, the earthing switch access hole must be blocked after only 1 ½ clockwise turns of the handle.

When the circuit breaker is in the �Test/Isolated� position or completely removed from the cubicle, it

should be possible to insert the earth switch operating handle through the access hole and onto the

hexagonal shaft of the earth switch.

It should now not be possible to rack the breaker into the �In Service� position and this action should be

blocked after only two clockwise turns of the handle.


Appendix 1: Abbreviations/Glossary of Terms

Abbreviation Full Description

ACH Anti-Condensation Heater

BES Busbar Earthing Switch

BIL Basic Impulse Insulation Level

CB Circuit Breaker

CT Current Transformer

EDPM Ethylene Propylene Diene Monomer (M-class rubber)

ES Earthing Switch

HDHC Hard Drawn High Conductivity

HV High Voltage

IAC Internal Arc Containment

IR Insulation Resistance

LV Low Voltage

MCB Miniature Circuit Breaker

MV Medium Voltage

VC Vacuum Contactor

VCB Vacuum Circuit Breaker

VT Voltage Transformer


Appendix 2: Related Documents

Document Reference Document Title Document

Origin

STD/CUS/003 Shipping, receiving, handling and storage procedure Powell UK

STD/CUS/007 Export Packing Specification Powell UK

STD/CUS/008 Packing/Unpacking Specification Powell UK

STD/CUS/009 Lifting Procedure Powell UK

STD/CUS/015 Current Transformer Powell UK

STD/DOC/012 Torque Settings Powell UK

STD/CUS/031 MV298 PowlVac100

TM Circuit Breaker Powell UK


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