Preparation Guide to CDMA2000 BSC6680 Engineering Installation

Preparation Guide to CDMA2000 BSC6680 Engineering Installation Internal

Applied Region Overseas Product Name CDMA BSC6680

Target readersCustomer / engineer /

cooperation partnerProduct Version V300R006

Edited by CDMA-BSS TSD Document Version 1.0

Preparation Guide to CDMA2000 BSC6680

Engineering Installation

Drafted

by：Liqi Date： 2009-09-18

Reviewed

by：Zhaochaozhong Date：

Approve

d by：Date：

Huawei Technologies Co, Ltd

All Rights Reserved

1

Preparation Guide to CDMA2000 BSC6680 Engineering Installation Customer

Revision Records

DateRevised

VersionDescription Author

2009-09-18 1.0 1、Finished the draft. Li Qi

2023-04-17 HUAWEI Confidential Page2, Total68


Table of Contents

Chapter1 Forward.........................................................................................................................5

Chapter2 Installation Procedure...................................................................................................6

Chapter3 Installation Requirements of CDMA2000 BSC6680...................................................7

3.1 Introduction of CDMA2000 BSS.......................................................................................7

3.1.1 Position of BSC in CDMA2000 System..................................................................7

3.2 Requirements for Layout and Space of the BSC Equipment Room....................................8

3.2.1 Requirements for Layout of the BSC Equipment Room..........................................8

3.2.2 Requirements for the Cabling Space of the BSC Equipment Room........................9

3.2.3 Requirements of Space for Capacity Expansion in the BSC Equipment Room.....11

3.3 Requirements for the BSC Equipment Room...................................................................13

3.3.1 Requirements for the Floor Conditions of the BSC Equipment Room..................13

3.3.2 Requirements for the Construction of the BSC Equipment Room.........................14

3.3.3 Requirements for the Working Environment of the BSC.......................................16

3.3.4 Basic Requirements for the Environment of the BSC............................................20

3.3.5 Requirements for Fire Protection in the BSC Equipment Room............................24

Chapter4 Preparations for Engineering Construction.................................................................25

4.1 Requirements for the Power Supply System of the BSC..................................................25

4.1.1 Power Supply Schemes for the BSC......................................................................25

4.1.2 Requirements for the DC Power Supply of the BSC.............................................26

4.1.3 Requirements for the AC Power Supply of the BSC.............................................27

4.2 Requirements for the Lightning Protection and Grounding of the BSC...........................29

4.2.1 Requirements for the Lightning Protection and Grounding System......................29

4.2.2 Underground Lightning Protection and Grounding System...................................31

4.2.3 Lightning Protection and Grounding of the Equipment Room..............................33

4.2.4 Outdoor Lightning Protection and Grounding System...........................................38

4.2.5 Lightning Protection and Grounding of the Power Supply System.......................41

4.2.6 Requirements for the Lightning Protection and Grounding of Signal Cables........43

4.2.7 Requirements for the Lightning Protection and Grounding of Feeders.................44

4.2.8 Requirements for Lightning Protection and Grounding of Other Equipment........46

4.3 Requirements for Transmission in the BSC......................................................................47

4.3.1 Physical Interfaces on the BSC..............................................................................47

4.3.2 Peer Equipment and Interfaces Supported by the BSC..........................................49

4.3.3 Requirements for the PDF/DDF/ODF....................................................................49

4.4 Requirements for BSC Cable Layout................................................................................50

4.4.1 Installation Specifications for Power Cables and PGND Cables...........................50

4.4.2 Cabling Specifications for the BSC Signal Cables.................................................51

4.5 Requirements for the Clock of the BSC............................................................................56

4.5.1 Clock Resources of the BSC..................................................................................56

4.5.2 Requirements for Clock Precision of the BSC.......................................................57

Chapter5 Checklist for BSC Site Preparation.............................................................................59

5.1 Checklist for the Site Location..........................................................................................59

5.2 Checklist for the Equipment Room Environment.............................................................59



5.3 Checklist for the Power Supply System............................................................................60

5.4 Checklist for the Grounding Cables..................................................................................61

5.5 Checklist for the Transmission System.............................................................................62

Chapter6 Physical and Electrical Parameters of CDMA BSC Switching Equipment.................63

6.1 Structure Specifications....................................................................................................63

6.2 Electrical Specifications....................................................................................................63

6.3 Specifications for GPS feeders and jumpers.....................................................................64

Chapter7 Physical and Electrical Parameters of M2000 OMC Equipment............................65



Chapter1 Forward

Dear Customer,

Thank you for your choice of Huawei Airbridge CDMA system. For the purpose of

better cooperation and successful installation, we compiled this Preparation

Guide to Airbridge CDMA BSS Installation. You are expected to have made good

preparations as required in this guide before Huawei technical engineers arrive

at the construction site. In this way, the equipment could successfully be put into

operation so as to bring social and economic benefits as early as possible.

Before the preparations for the installation, you should carefully read the

following contents:

After you finish all the preparations for the installation, please contact the

regional office in time so that Huawei could arrange engineers for the

engineering installation.

If the installation starts in the case that the preparations are not fully completed

for some reason, you should arrange personnel to prepare for the unsatisfied

conditions as early as possible so as to carry out the installation successfully.

If the installation starts in the case that the preparations are not fully completed

for some reason, but it is impossible for the installation to continue due to the

inadequacy of preparations, Huawei has the right to stop the installation,

depending on the specific situation. After the preparations get fully ready, both

parties can negotiate to arrange for the restart of installation.

If you have any question during the preparations for the installation, please feel

free to consult the regional office of Huawei.

The following lists the information about the regional office of Huawei for your

reference:

Address:

Telephone/fax:

Project owner and telephone:

5


Chapter2 Installation Procedure

The installation procedure for Huawei equipment is introduced here for the purpose of a better

understanding and cooperation between both parties. The installation procedure starts with the

signing of the contract and ends with the final acceptance of equipment, followed by the

maintenance procedure. The installation procedure is shown below:

A successful completion of a project requires the close cooperation between you and Huawei. We

hope the installation can successfully be completed.

6


Chapter3 Installation Requirements of

CDMA2000 BSC6680

3.1 Introduction of CDMA2000 BSS

3.1.1 Position of BSC in CDMA2000 System

PCF：Packet Control Function PDSN：Packet Data Serving Node

HA：Home Agent FA：Foreign Agent

MS：Mobile Station SCP：Service Control Point(Intelligent

Network)Radius：Remote Authentication Dial-in User

Service Figure3-1 CDMA2000 System Structure

The CDMA system consists of several subsystems or functional entities. The base station

subsystem (BSS) is closely related to the wireless cellular technology in the CDMA system.

7


Through the radio interface, the BSS connects the MS to send and receive radio signals and

manage radio resources. The BSS connects the mobile switching center (MSC) in the network

subsystem (NSS) to transfer system signals and user information between mobile subscribers, or

between mobile subscribers and PSTN subscribers. On the other hand, the BSS connects the

packet data serving node (PDSN) to realize the packet data service.

3.2 Requirements for Layout and Space of the BSC

Equipment Room

3.2.1 Requirements for Layout of the BSC Equipment Room

This topic describes the requirements for ensuring appropriate layout, easy installation, and

neatness in a BSC equipment room.

The requirements for the layout of the BSC equipment room are as follows:

The minimum distance between the front portions of two adjacent cabinet rows

should be 1,800 mm [5.91 ft].

The minimum distance between a wall and a cabinet side that is closest to the wall

should be 800 mm [2.63 ft].

The minimum distance between a wall and the front or the back of its closest cabinet

row should be 800 mm [2.63 ft].

An aisle that is at least 1,000 mm [3.28 ft] wide should be reserved in the equipment

room.

The minimum head room of the equipment room should 3000 mm [9.84 ft].

If the BSC cabinets, BSC cabinets, and PDF are co-located in an equipment room,

Huawei recommends that all the cabinets be installed in one row for facilitating

cable routing.

Figure3-2 shows the layout of the BSC equipment room.

8


Figure3-2 Layout of an equipment room (unit: mm)

The layout of the equipment room should be completed by the design department of the

customer or survey engineers, and copies of the layout should be provided to Huawei before

the delivery of products.

3.2.2 Requirements for the Cabling Space of the BSC Equipment

Room

This topic describes the requirements for the cabling space of the BSC equipment room,

where both overhead cabling and underfloor cabling can be used.

9


Overhead Cabling in the BSC Equipment Room

When overhead cabling is used in the BSC equipment room, the following requirements must

be met:

The minimum distance between the roof and the top of the cabinet should be 1 m

[3.28 ft].

A 200-mm wide space should be kept at both ends of each cabinet row for the

installation of cable racks.

Figure3-3 shows the overhead cabling in an equipment room.

Figure3-3 Overhead cabling in a BSC equipment room (unit: mm)

Underfloor Cabling in the BSC Equipment Room

When underfloor cabling is used in the BSC equipment room, the height of the ESD floor

should be greater than 200 mm [7.87 in.], as shown in Figure3-4.

10


Figure3-4 Underfloor cabling in a BSC equipment room (unit: mm)

NOTE:

The height of the ESD floor refers to the distance between the upper surface of the ESD

floor and the surface of the cement floor.

If some of the above conditions cannot be met, you can route the cables based on the

actual situation. Appropriate cable racks, however, must be kept ready.

3.2.3 Requirements of Space for Capacity Expansion in the BSC

Equipment Room

This topic describes the requirements of space for capacity expansion in the BSC equipment

room.

Space Reservation for a Fully-Configured System

A fully-configured BSC consists of one CBCR and one CBSR..

Figure3-5 shows the space reserved for a fully-configured system.

11


Figure3-5 Space reserved for a fully-configured system (unit: mm)

12


3.3 Requirements for the BSC Equipment Room

3.3.1 Requirements for the Floor Conditions of the BSC

Equipment Room

This topic describes the requirements for the floor conditions of the BSC equipment room,

including the requirements for the floor type and the requirements for the height of the

equipment room.

Requirements for the Floor Type of the Equipment Room

The BSC can be installed either on a cement floor or on an ESD floor.

Table3-1 lists the requirements for the floor conditions of the BSC equipment room.

Table3-1 Requirements for the floor conditions of the equipment room

Floor Type Requirements for the Floor Conditions

Cement floor The weight-bearing capacity of the equipment room should be

equal to or greater than 450 kg/m2.

The thickness of the floor should be greater than the length of the

expansion bolt assembly.

ESD floor The resistance of the ESD floor must comply with the relevant

requirements.

The floor is firm and tight, with a horizontal error less than 2 mm

[0.08 in.] per square meter.

If an ESD floor is not available, use a static-conductive floor

instead. The volume resistivity of the static-conductive floor must

range from 1.0 x 107 ohms to 1.0 x 1010 ohms.

The floor should be connected to the grounding device through a

current-limiting resistor and cables. The resistance of the resistor

must be 1 Mohms. Tests show that terrazzo (including cement floor)

can met the requirements mentioned above.

All the cable holes should be covered with lids. Ensure that the

13


Table3-1 Requirements for the floor conditions of the equipment room

Floor Type Requirements for the Floor Conditions

location and size of the holes comply with the engineering design.

Requirements for the Height of the Equipment Room

Locate the equipment room on or above the second floor or at least 600 mm [23.62 in.] above

the maximum flood level recorded in the local area.

3.3.2 Requirements for the Construction of the BSC Equipment

Room

This topic describes the requirements for the BSC equipment room. The equipment room

consists of the switching room, control room (with an area not smaller than 20 m 2[215.273 ft 2]), and auxiliary room. If required, the switching room and the control room can be combined.

During the construction of an equipment room, factors such as cabling (shortest routing of

antenna cables), weight-bearing capacity, power supply, and entrance of transmission cables

must be considered.

Requirements for the Area

The requirements for the area of an equipment room are as follows:

The area must have the scope for future capacity expansions.

The area must facilitate feeder window installation and feeder distribution.

The area must facilitate installation and maintenance of the equipment.

There should be enough space for opening and closing the doors of cabinets.

The actual area of an equipment room depends on the network capacity. For specific

requirements, consult with Huawei survey engineers when planning the layout the equipment

room.

14


Requirements for the Height

The minimum height of the equipment room, which refers to the distance between the beam

or the wind pipe and the floor, should be 3.5 m [11.48 ft] for overhead cabling and 3 m [9.84

ft] for underfloor cabling. Thus, sufficient space can be reserved for installing the cable rack

and laying cables and feeder pipes.

Requirements for the Weight-Bearing Capacity

The weight-bearing capacity of the equipment room depends on the equipment weight,

equipment base area, installation position, and structure of the equipment room. Ensure that

the weight-bearing capacity is tested by a construction engineer. If the capacity does not meet

the requirements, take appropriate measures to increase the weight-bearing capacity.

Generally speaking, The weight-bearing capacity of the equipment room should be equal to or

greater than 450 kg/m2.

Requirements for the Doors and Windows

The requirements for the doors and windows of the equipment room are as follows:

The size of the doors should be appropriate. Each door should have a lock and key.

Doors and windows should be sealed with anti-dust rubber strips.

Windows exposed to direct sunlight should be covered with reflecting paper or

colored glass. If the sunlight in the room is sufficient, you can block the windows.

Doors and windows should be firm and dustproof. The roof should be waterproof and

dustproof, and the materials used should not be combustible.

Requirements for the Roof and Walls

The requirements for the roof and walls of the equipment room are as follows:

The roof and walls should be heat-insulating and waterproof.

The roof should be waterproofed if there are antenna mast and cable holes in the

roof. Ensure that the roof has the required weight-bearing capacity.

The walls can be painted with lusterless lacquer rather than the paint that easily

chalks.

The roof and walls should be light-colored.

15


Requirements for Resistance

The intensity requirement of shockproof design of the equipment room should be one degree

higher than the local intensity requirement. If the shockproof design is not satisfactory,

strengthen the construction of the equipment room.

Requirements for Lightning Protection and Grounding

For details, refer to 4.2.3 Lightning Protection and Grounding of the Equipment Room.

Requirements for Dustproofing

The requirements for dustproofing are as follows:

The density of the dust with a diameter greater than 5 micron should be less than

3×104granule/m3.

The dust granules should be non-conductive, non-magnetic, and non-corrosive.

Huawei recommends that the following measures should be taken to make the equipment

room dustproof:

Ensure that the doors and windows are airtight. Equip the outer windows with double-

layer glass and the doors with sealing strips.

Ensure that the shoes and clothes that are used in the equipment room are clean and

washed regularly.

Isolate the control room from the switching room by using aluminum alloy frames with

glass. To prevent dust or any other possible interference, do not allow personnel

from frequently entering the switching room.

If possible, increase the humidity of the equipment room because higher humidity can

reduce static electricity.

Requirements for the Passageway

The requirements for the passageway of an equipment room are as follows:

The width of the transmission passageway should be more than 1.5 m [4.92 ft] and its

height should be more than 2.5 m [8.20 ft].

All the emergency exits in the equipment room should be free from obstructions.

Emergency exit signs should be placed at prominent locations.

The height of the doors of the equipment room should be more than 2 m [6.56 ft] and

their width should be more than 1 m [3.28 ft].

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The height of the elevator should greater than 2.4 m [7.87 ft].

3.3.3 Requirements for the Working Environment of the BSC

This topic describes the requirements for the working environment. The requirements for the

working environment consist of the climatic, waterproof, ESD, biological, air cleanness, and

mechanical stress requirements.

Requirements for Climate

Table3-2 and Table3-3 list the climatic requirements of the BSC.

Table3-2 Requirements for temperature and humidity

Temperature Relative Humidity

Long-term Short-term Long-term Short-term

0℃ to 45℃ -5℃ to +55℃ 5% to 85% 5% to 95%

NOTE:

Measure the temperature and humidity at the place 1.5 m [4.92 ft] above the floor

and 0.4 m [1.31 ft] in front of the cabinet (no protection boards in front or at the rear of

the cabinet).

Short-term refers to a period of less than 96 continuous hours or less than 15 days

in a year.

Table3-3 Other climatic requirements

Item Range

Altitude ≤ 4,000 m [2.48 miles]

Air pressure 70 kPa to 106 kPa

Temperature change rate ≤ 3℃/min [37.40 °F/min]

Solar radiation ≤ 700 W/m2

17


Table3-3 Other climatic requirements

Item Range

Heat radiation ≤ 600 W/m2

Wind speed ≤ 5 m/s

To meet the above requirements, take the following measures:

Use dustproof materials for the floor, walls, and roof.

Install screen doors and screen windows. Ensure that the outer windows are

dustproof.

Clean the equipment room and air filter regularly (for example, once every three

months).

Wear ESD-preventive shoes and uniforms before entering into the room.

Requirements for the Biological Environment

The working environment of the BSC should meet the following biological requirements:

The environment should not be conducive to the proliferation of fungus or mildew.

There should not be any rodents such as mice.

Requirements for Air Cleanness

The working environment of the BSC should meet the following requirements for air

cleanness:

The air should be free from explosive, conductive, magneto-conductive, or corrosive

dust.

The density of physically active materials must comply with the requirements listed in

Table3-4.

The density of chemically active materials must comply with the requirements listed in

Table3-5.

18


Table3-4 Requirements for physically active materials

Chemically Active Material Unit Density

Dust particles granule/m3 ≤ 3 x 104 (No visible dust on

desks within three days)

NOTE:

Dust particles: diameter ≥ 5 μm

Table3-5 Requirements for chemically active materials

Chemically Active

Materials

Unit Density

SO2 mg/m3 ≤ 0.20

H2S mg/m3 ≤ 0.006

NH3 mg/m3 ≤ 0.05

Cl2 mg/m3 ≤ 0.01

Requirements for mechanical stress

The mechanical stress of the working environment of the BSC should meet the requirements

listed in Table3-6.

Table3-6 Requirements for mechanical stress

Item Sub-Item Range

Sinusoidal vibration Offset ≤ 3.5 mm [0.14 in.] -

Accelerated speed - ≤ 10.0m/s2

19


Table3-6 Requirements for mechanical stress

Item Sub-Item Range

Frequency range 2 Hz to 9 Hz 9 Hz [9 c/s] to 200 Hz

[9 c/s]

Unsteady impact Impact response

spectrum II

≤ 100 m/s2

Static payload 0

NOTE:

Impact response spectrum refers to the maximum acceleration response curve

generated by the equipment under specified impact excitation. Impact response

spectrum II means that the duration of the semi-sine impact response spectrum is 6

ms.

Static payload refers to the capability of the packed equipment to bear the pressure

from the top in normal pile-up method.

3.3.4 Basic Requirements for the Environment of the BSC

Requirements for ESD Prevention

The absolute value of electrostatic voltage should be less than 1,000 V. To meet the above

requirement, take the following measures:

Train the operators on ESD prevention.

Control the humidity in the room to reduce static electricity.

Equip the equipment room with an antistatic floor or ground the floor properly.

Wear ESD-preventive shoes and uniforms before entering into the room.

Use antistatic tools such as ESD-preventive wrist straps, antistatic tweezers, and

extraction tools during operations.

Ground all the conductive devices (including computer terminals) in the room and

arrange for antistatic workbenches.

20


Keep non-antistatic materials such as common bags, foams, and rubbers at least 30

cm [0.98 ft] away from boards and ESD-sensitive devices.

Requirements for Anti-Interference

With the development of sciences and technology, interference sources that produce stray

signals have increased rapidly. The stray signals affect communications quality and the

normal operation of the BSC equipment. The possible interference sources are listed as

follows:

Corona discharge of transmission lines

Electromagnetic interference caused by transformers

Various kinds of switch apparatuses

Waveform distortion due to operation on large-sized equipment

Radio-frequency interference

Natural interference such as the terrestrial magnetic field and extraneous radiation

The possible forms that interference takes are capacitance coupling, inductive coupling,

electromagnetic wave radiation, electric conduction of common resistance (including the

grounding system), and electric conduction of various conducting wires (power cables, signal

cables, and output cables).

When external noises exceed the anti-interference capacity of the integrated circuit of

equipment, the equipment may not operate normally. It is impossible to eliminate or shield all

the interference. You can, however, reduce the interference by taking the following measures:

High-frequency interference signals on electric networks are generated by the

coupling of primary coil to secondary coil of the power transformer through the

distributed capacitor. Thus, a low pass filter on led-in power cables and a proper

power transformer can suppress the interference.

To remove the interference caused by the grounding system, prevent various

grounds (signal ground, power ground, protection ground, and shielding ground)

from forming loops, such as the loop formed by a large distributed capacitor. If loops

exist, interference signals affect the normal operation of the equipment through the

coupling of the common resistance of the grounding system.

Protecting the equipment against electromagnetic interference

In some multiple-use buildings, there may be more than one high-frequency

transmitter, whose impact on the BSC equipment must comply with the

requirements specified in the related EMC standards. In addition, make sure that

you ground, shield, and filter the waves for the BSC equipment properly.

21


In a high-frequency electromagnetic field (external interference), a high longitudinal

voltage may be inducted in the sheath and the core of the communication cable.

Due to the asymmetry of the core, the longitudinal voltage may generate lateral

noise voltage at the end of the core. The noise voltage causes interference. If the

metallic sheath is grounded, the sheath produces the shield function and the

longitudinal voltage decreases significantly, and the interference voltage is reduced.

Additionally, interference reduction can be achieved through the following methods:

lowering the voltage and current of interference sources, shortening the wires or the

interval of wires for decreasing the area of the interference loop, placing insulated

and interfered wires on the grounded surface, using special ground return cable for

eliminating common resistance, and twisting signal cables and return cables

together for offsetting the partial external electromagnetic interference. All the

methods mentioned earlier are effective.

The density of the electric field in the equipment room must not exceed 300 mV/m.

The density of the magnetic field must not exceed 11 GS.

Requirements for Illumination

The requirements for illumination in the equipment room are as follows:

The equipment room must not be exposed to direct sunlight. Exposure to direct

sunlight can lead to the aging and deformation of circuit boards and other

components.

The battery compartment should be equipped with an explosion-proof lamp that does

not emit bright light.

If the sunlight in the room is sufficient, you can paint or block the windows.

For BSC equipment rooms that have large capacity or great influence, a DC power

supply should be arranged as the standby lighting system.

Requirements for Air Conditioning

Calculate the capacity of the air conditioner based on the area of the equipment room and the

heat emitted by the BSC equipment. For the calculation method, refer to relevant engineering

design specifications.

Generally, you can use two air conditioners so that they can work alternately.

The following equation is used to calculate the heat emitted in the BSC equipment room:

Q = 0.86 x (V x A – W) (kilocalorie/hour)

Where,

Q refers to the heat emitted by the BSC equipment.

22


V (in volts) refers to the voltage of the DC power supply.

A (in amperes) refers to the average power consumed in a busy hour.

W (in watts) refers to the effective radiating power of the antenna.

The number 0.86 is the conversion coefficient of electrical energy per watt to heat

energy.

If the BSC equipment room has other telecommunication devices, heat emitted by these

devices should be considered.

The requirements for the air conditioners in the equipment room are as follows:

Humidity: 30% to 75% (50% to 60% preferred.)

Temperature: 18°C to 28°C (20°C to 25°C preferred)

Requirements for Communication

Telephones and facsimile machines should be available in the equipment room.

Requirements for the Environment Control System

The environment control system consists of the timing control, temperature monitor, anti-theft

alarms, smoke alarms, and power supply and backup power control. The system must meet

the following requirements:

The working time and working mode of the air conditioner should be adjusted

automatically according to the measured temperature.

Intrusion, over-high temperature, AC power failure, smoke, and fires, and transfer of

the alarm information to the O&M center should be detected, thus realizing remote

maintenance for the BSC.

Table3-7 lists the requirements for the environment control system.

Table3-7 Requirements for the environment control system

Item Requirement

Timing control According to the time preset based on BSC, the system controls the

timing converter to automatically convert the working states of the air

conditioners. The air conditioners work in turns, and thus the energy

is saved and the life span of the air conditioners is prolonged.

Temperature Detects the temperature in real time and generates alarms when the

23


Table3-7 Requirements for the environment control system

Item Requirement

monitoring temperature exceeds the thresholds.

Anti-theft alarm Detects the intrusion into the equipment room in real time. The dual-

mode detection annunciator (infrared and microwave) is

recommended.

Smoke alarm Detects smoke or fires in the equipment room in real time.

Power supply and

backup power control

Automatic charging

When the battery detection circuit detects that the power is

insufficient, the system should switch to the automatic charging

state.

Charging protection

The system protects the batteries in the case of abnormal

power supply or over-high charge current.

Discharging protection

The system cuts off the load when the battery charge level

drops and the life span of the battery is affected.

The battery should provide power supply when there is a

power failure. When the mains supply becomes available, the

system should switch back to the mains supply state and the

charging state.

3.3.5 Requirements for Fire Protection in the BSC Equipment

Room

This topic describes the requirements for fire protection in the equipment room.

For buildings with fire resistance rating 1 or 2, the minimum space between buildings should

be 6 m [19.68 ft]. For buildings with fire resistance rating 3 or 4, the minimum space between

buildings should be 7 m [22.96 ft].

Flammable and explosive materials should be kept away from the equipment room.

24


Fire extinction facilities must be available on the construction site. Alarm devices,

such as smoke sensors and temperature sensors, must be functional.

Sockets of different voltages should be marked noticeably.

Reserved mounting holes in the floor should be installed with safety covers.

If possible, automatic fire extinguishers should be installed. In addition, portable extinguishers

must be available along the aisle of the equipment room.

The water pool for fire extinction should hold sufficient water to extinguish the fire both outside

and inside the room (assuming that the fire lasts for 2 hours). Fire hydrants should be placed

where they are easily accessible. Do not place them inside the room.

25


Chapter4 Preparations for Engineering

Construction

4.1 Requirements for the Power Supply System of the BSC

4.1.1 Power Supply Schemes for the BSC

This topic describes the power supply system of the BSC. The power supply system consists

of DC power distribution cabinet, PDB, and cables that connect them.

For a large-capacity site or a site with more than two switching systems, provide each of them

with an independent power supply system.

In large-sized communications venues, you should install multiple independent power supply

systems that supply power to the equipment rooms on different floors.

In middle-sized communication offices, you should use either integrated power supply or

dispersed power supply. In small-sized offices, the integrated power supply can be used.

Ensure that the circuit boards are protected from the corrosive gases emitted by the batteries.

Figure4-1 shows the power supply system for the BSC.

26


Figure4-1 Power supply system for the BSC

4.1.2 Requirements for the DC Power Supply of the BSC

This topic describes the requirements for the DC power supply of the BSC. To provide stable

and reliable power supply and to shorten the DC feed route as much as possible, you should

place the power equipment close to the telecommunications equipment. To reduce power

consumption and installation cost, ensure that the loop voltage drop between the battery port

and the port on the equipment is less than 3.2 V.

Table4-1 lists the requirements for DC power supply.

Table4-1 Requirements for DC power supply

Item Description

Permissible

range of the

input voltage

–57 V DC to –40 V DC

Bearing

capability for

surge current

At least 1.5 times of the rated current

27


Table4-1 Requirements for DC power supply

Item Description

Regulated

voltage

precision

If the input AC voltage ranges from 85% to 110% of the rated value, and the

load current ranges from 5% to 100% of the rated value, the output voltage of

the rectifier ranges from –46.0 V to –56.4 V, with the regulated voltage

precision of the rectifier no more than 1%.

On/off

overshoot

amplitude

The switch on/off overshoot amplitude should be equal to or less than ±5% of

the output DC voltage.

Peak-to-peak

noise voltage

≤ 200 mV

Dynamic

response

The restore time is less than 200 ms, with the overshoot amplitude not

exceeding ±5% of the output DC voltage.

The requirements for the DC power supply system are as follows:

The dispersed power supply mode is recommended, that is, multiple DC power

supply systems and power devices can be used.

A standard DC power supply system should be used and the output voltage should

meet the related requirements.

To improve the reliability of the whole power supply system, you should improve the

reliability of the AC power supply system and reduce the battery capacity. If the

reliability of the AC power supply system is difficult to improve, you can increase the

battery capacity.

The capacity of the high-frequency switch rectifier must meet the needs of power of

the equipment and the charging power of the battery. If the number of active

rectifiers is less than 10, use one standby rectifier. If the number is greater than 10,

use one standby rectifier for every 10 active ones.

The batteries should be divided into two or more groups. The battery capacity

depends on the service time of the battery groups that provide power to the system

independently. In most communication offices, the battery group should be able to

power the system for at least one hour.

28


4.1.3 Requirements for the AC Power Supply of the BSC

This topic describes the requirements for the AC power supply of the BSC. AC power should

be ready before the construction of the equipment room.

CAUTION:

To ensure the smooth operation of the maintenance terminal in the event of power failure,

UPS should be available.

The centralized power supply mode is preferred for the AC power supply system that consists

of the mains, UPS, and electrical generator.

CAUTION:

The AC backup power and the mains supply must be synchronized in phases, and the

UPS/mains switchover duration must be shorter than 10 ms. If not, the equipment may be

reset or restarted.

In a low-voltage power supply system, three-phase power or single-phase power is preferred.

Table4-2 lists the nominal voltage and frequency of low-voltage AC power.

Table4-2 Nominal voltage and frequency of low-voltage AC power

Nominal Voltage (Unit: V) Nominal Frequency (Unit: Hz)

110, 127, 200, 220, 230, 240, or 380 50 or 60

NOTE:

Power supply systems vary with countries, regions, or areas. For example, a country may use

the three-phase three-wire of 200 V, three-phase four-wire of 200 V, or single-phase three-

wire of 200 V power.

When you determine the AC power distribution capacity in the equipment room, consider the

working current and faulty current to ensure that individual equipment has an independent AC

distribution protection device. The protection switch should be more powerful than that of the

lower-level electricity devices. Cable outlet of the power distribution panel is determined by

the maximum load capacity of power supply. The type and specification of cables are chosen

accordingly.

29


The following lists the specific requirements for the AC voltage of communications equipment

and power supply equipment:

If the communications equipment uses the AC power supply, the permissible voltage

range should be –10% to +5% of the nominal voltage.

If the power supply equipment and important buildings uses the AC power supply, the

permissible voltage range should be –15% to +10% of the nominal voltage.

The permissible fluctuation range of AC frequencies should be within ±4%. The

sinusoidal distortion rate of the voltage waveform should be lower than or equal to

5%.

The requirements for the electrical generators are as follows:

No loud noise

Automatic power-on and power-off, supply, and communication

Remote control and measurement

Standard interfaces and communication protocols

The requirements for the AC power cables are as follows:

For the AC neutral for communications, the conducting wire should have the same

cross-sectional area as the phase line.

The AC conducting wires should be fire-resistant. The layout of the AC power cables

must comply with local regulations.

The requirements for the AC power supply system are as follows:

Use the voltage regulator in any of the following situations:

The communications equipment is powered directly by the mains supply, and

the input voltage exceeds the nominal voltage by –10% to +5% or exceeds the

permissible voltage range for the communications equipment.

The communications equipment is not powered directly by the mains supply,

but the mains voltage exceeds the nominal voltage by –15% to +10% or

exceeds the permissible AC input voltage for the DC power supplier.

A UPS or inverter should be used to ensure stable power supply.

An electrical generator should be configured for the office to ensure proper

communication in the event of mains failure. The minimum capacity of the generator

should be 1.5 to 2 times of the total capacity of the UPS and the inverter.

The capacity of the UPS or inverter must be greater than the total load power,

preferably with a surplus of 80% of the total load power. Backup is required for the

use of the UPS or inverter.

30


4.2 Requirements for the Lightning Protection and

Grounding of the BSC

4.2.1 Requirements for the Lightning Protection and Grounding

System

This topic describes the basic requirements for grounding and the requirements for the

grounding resistance, grounding of the DC power distribution system, equipotential

grounding, and lightning rod.

Basic Requirements for Grounding

The basic requirements for grounding are as follows:

The neutral lines of AC power cables must not be connected to the protection ground

of any communications devices.

All grounding cables must be short and straight. The grounding cables cannot be

twisted.

Fuses or switches must not be installed on grounding cables.

The grounding cables should be securely connected to the protection grounding bar

of the equipment room. In case of oxidation, bad contact may be caused between

the grounding cables and the grounding bar, thus increasing the resistance.

Requirements for the Grounding Resistance

CAUTION:

The joint grounding system should interconnect the working ground, the protection

ground, the grounding system of the building, and the grounding system of the industrial

frequency AC power supply.

The grounding resistance must meet the requirements specified by local countries or

telecommunication operators.

The requirements for the grounding resistance are as follows:

31


The grounding resistance of the joint grounding system must be less than or equal to

10 ohms.

For other devices in the equipment room, the lowest grounding resistance should be

applied.

Requirements for the Grounding of the DC Power Distribution System

The DC working ground (reflow ground of the –48 V DC or +24 V DC power supply) must be

connected with the indoor grounding bar nearby. The grounding cable must be capable of

supporting the maximum load of the system.

Requirements for Equipotential Grounding

The requirements for equipotential grounding are as follows:

All the equipment and auxiliary facilities in the equipment room must be grounded

properly.

All the protection grounds must be connected to a grounding bar, and the protection

grounds in an equipment room must be connected to the protection grounding bar of the

equipment room.

The working grounds and protection grounds must share the same group of

grounding grids.

The grounding grids for the equipment room, tower, and power transformer must be

interconnected underground in a multi-point manner. If the tower is located on the roof of

the equipment room and the power transformer is located in the equipment room, the

tower and the power transformer can share the grounding grid of the equipment room.

Figure4-2 shows the grounding grids.

Figure4-2 Grounding grids

The cable rack, steel shelf, rack or chassis, metallic air conduit, and metallic window

and door must be properly grounded.

32


Requirements for the Lightning Rod

The antenna of the base station must be protected by the lightning rod, that is, the antenna

must be located within the protection range of the lightning rod.

The lightning rod must have a special surge current leadin, which is made from 40 mm [1.57

in.] x 4 mm [0.16 in.] galvanized flat steel.

4.2.2 Underground Lightning Protection and Grounding System

This topic describes the requirements for the underground lightning protection and grounding

system.

Various grounding copper bars are connected to the grounding grid through copper cables.

The sectional area of cables must meet the local or national requirements.

Figure4-3 shows the underground grounding grid.

Figure4-3 Underground grounding grid

NOTE:

You can arrange for a grounding bar in the equipment room. The indoor rack grounding bar,

AC grounding bar, and DC grounding bar are connected to the grounding bar.

The requirements for the grounding facilities shown in Figure4-3 are as follows:

33


The grounding grids for the power transformer, steel tower, and equipment room form

a uniform grounding grid. The grounding grid must be connected to at least two steel

bars of the building and tower.

The outdoor grounding ring can be connected in an L-shape or a C-shape. In areas

where the soil has a low conductivity or there is a shortage of soil, use grounding stretch

body. The grounding stretch body is a concrete bridge with built-in cables. It stretches

outward from the corners of the grounding ring. The concrete bridge has strong moisture

absorption capability. The recommended length of the grounding stretch body is 10 m

[32.81 ft] to 30 m [98.42 ft].

It is recommended to use hot galvanized steel grounding pole with the specifications

as follows:

Steel tube: φ50 mm [1.97 in.], and greater than 3.5 mm [0.14 in.] in thickness

Angle steel: no less than 50 mm [1.97 in.] x 50 mm [1.97 in.] x 5 mm [0.197

in.] in volume

Flat steel: no less than 40 mm [1.57 in.] x 4 mm [0.16 in.] in size

Length: 1.5 m [4.92 ft] to 2.5 m [8.20 ft]

The space between the grounding poles is 1.5 to 2 times the length of a grounding pole.

The upper end of the grounding pole should be more than 0.7 m [2.30 ft] from the

ground surface. In cold areas, the entire grounding pole should be buried under the

frozen soil layer.

The grounding ring should be buried 0.7 m [2.30 ft] into the cement base.

Whether to use resistivity reduction mixture depends on the location of the equipment

room and the status of the soil.

4.2.3 Lightning Protection and Grounding of the Equipment

Room

This topic describes the requirements for the lightning protection and grounding system of the

equipment room. The system consists of the indoor grounding bar, cable rack, grounding

leadin, earth electrode, and grounding resistance.

Overview

The grounding copper bars are available in the equipment room.

34


In areas where lightning strikes frequently, the overhead bare wire ring on the internal wall of

the equipment room must also be grounded indoors. Several parts of the wire ring are

connected to the outdoor port of the grounding system. The wire ring is used to ground the

conductors of the door and window.

Figure4-4 shows the grounding system of the equipment room.

Figure4-4 Grounding system of the equipment room

NOTE:

Arrange for a grounding bar to interconnect the protection grounds and the working

ground of the devices in the equipment room.

Use 40 mm [1.57 in.] x 4 mm [0.16 in.] or 50 mm [1.97 in.] x 5 mm [0.20 in.] galvanized

flat steel as the grounding leadin. Take protective measures for the projecting parts of

the grounding leadin.

Indoor Grounding Bar

The indoor grounding bar is generally installed on a wall. The wall near the base station and

power supply cabinet is used and it is as high as the cable rack. A single black grounding

cable connects the grounding bar to the earth electrode.

Cable Rack

The indoor cable rack is connected to the indoor grounding bar by using a cable.

The indoor cable rack must be connected separately from the outdoor cable rack.

35


Both ends of the cable rack must be properly grounded.

When the connectors between the cable racks are not connected properly, add

cables to improve the electrical connection between the cable racks.

Grounding Lead-In

CAUTION:

The same metal material should be used for the entire lightning protection system that

consists of the lightning rods, lead-in, and grounding body. This prevents corrosion and

poor grounding owing to long-term electrochemical reaction.

The copper should not contact the galvanized iron parts directly because copper-zinc

battery may be formed on the contact surface and thus cause corrosion.

The flat braided wires or bunched wires cannot be used as the grounding lead-ins. They are

susceptible to corrosion and oxidation. In addition, they have strong electric inductance and

mutual inductance, thus affecting surge current discharge.

The grounding lead-in should use galvanized flat steel or φ16 to φ18 screw-thread steel.

The grounding lead-in must be welded with the lightning rods and the grounding body. The

contact seam must be longer than 20 cm [7.87 in.]. Otherwise, high current passing through

the seam can make the small contact area hot and probably cause serious sealing-off.

When the grounding cable is led down from the roof,

do not arrange the cable near or in parallel with other conductors. Regardless of

whether the other conductors are grounded, the space between the grounding cable

and the conductors must be more than 2 m [6.56 ft].

When the grounding lead-in has to pass through a metallic tube,

connect the two ends of the lead-in to the two ends of the metallic tube. This

metallic tube is also called the connection cable of the grounding cable.

NOTE:

The earth electrode under the steel tower must be as close as possible to the bottom of the

steel tower.

Earth Electrode

NOTE:

The grounding resistance is the sum of the drifting resistance of grounding bodies and

the resistance of grounding cables.

36


The drifting resistance is the resistance of the grounding body and the resistance in the

soil within the reach of 20 m [65.62 ft] around the grounding body.

If the grounding cable is not too long, ignore its resistance.

The grounding resistance must be less than or equal to 10 ohms.

The formula for calculating the DC or industrial frequency drifting resistance varies according

to the types of earth electrodes, the number of grounding poles, and the forms of

combination. The following part lists some of the formulas that are used to estimate the

grounding resistance of commonly used earth electrode sets:

Single piece of steel pipe vertical bar

If the earth electrode of steel pipe has a length of 2.5 m [8.20 ft], a diameter of 5 cm

[1.97 in.], and a buried depth of more than 0.5 m [1.64 ft] (from the top of the tube to the

ground), you can use the following formula to calculate its grounding resistance:

R ≈ 0.3ρ (ohms)

ρ: resistivity of soil

A horizontal flat steel band

When the length of the flat steel band is about 60 cm [23.62 in.], its grounding resistance

is defined as:

R ≈ 0.03ρ (ohms)

Parallel earth electrode set constituted by four steel pipes

The grounding resistance is defined as:

R ≈ 0.051ρ (ohms)

The vertical grounding poles of the earth electrode set use four steel pipes

with a length of 2.5 m [8.20 ft] and a diameter of 5 cm [1.97 in.]. Its depth in the soil

is 0.5 m [1.64 ft]. The space between the pipes is 5 m [16.40 ft], and the horizontal

connecting wires between these tubes are 40 mm x 4 mm [1.57 in. x 0.16 in.]

galvanized flat steel bars, as shown in Figure4-5.

Figure4-5 Parallel earth electrode set constituted by four steel pipes

Rectangular earth electrode set constituted by six steel pipes, as shown in Figure4-6.

37


Figure4-6 Connection of vertical grounding poles of the earth electrode set

As shown in Figure 4-6, the steel pipes are the same as those in the parallel earth

electrode set. The grounding resistance is defined as:

R ≈ 0.045ρ (ohms)

In this formula, soil resistance is the key factor. The actual soil resistivity can be

measured by using a grounding resistance tester on site. If the actual value cannot be

obtained, refer to the values listed in Table4-3.

Table4-3 Resistivity of soils

Soil Type Resistivity (ρ/ohm·m)

Sea water 1 to 5

Kaolin 10

Peat and marshland 20

Lake water and pond water 30

Black soil, garden loam, malm, and pottery

clay

50

Clay 60

Sandy clay 100

Concrete in wet soil 100 to 200

Loess 200

Sandy clay and sandy soil 300

38


Table4-3 Resistivity of soils

Soil Type Resistivity (ρ/ohm·m)

Rocky soil 400

Topsoil mixed with stones and under-layer

gravel (humidity: 15% RH)

500

Sands and clay soil (with a depth less than

1.5 m [4.92 ft], and being rocky at the bottom

layer)

1000

Gravel, detritus, and rock mountain 5000

Granite 20000

The impact grounding resistance (Rch) equals to the DC grounding resistance

multiplied by the impact factor, where:

Rch = αR (ohms)

R indicates the DC (or industrial frequency) grounding resistance.

α is the impact coefficient.

The impact coefficient is related to the shape and size of the earth electrode, the

impact current, and the resistivity of the soil. The value of α ranges from 0.25 to

1.25. For a tabular vertical grounding body, the value of α ranges from 0.25 to 0.9.

NOTE:

The type and temperature of the soil around the grounding pole affect the grounding

resistance. To improve the grounding resistance, do as follows:

In areas where the soil conditions are poor, the chemical resistance-reducing agent (for

example, acrylamide resistance-reducing agent) can be added around the grounding

pole.

In the high-latitude areas where the soil temperature is below 0oC, the grounding pole

can be deeply buried and chemical resistance-reducing agent can be added.

39


4.2.4 Outdoor Lightning Protection and Grounding System

This topic describes the outdoor grounding system, the lightning protection and grounding of

the RF antenna system, and the lightning protection and grounding of the satellite antenna

system.

Overview

The outdoor lightning protection and grounding system consists of the grounding of the

building, the grounding of the steel tower, and the grounding of the antenna system. The

outdoor grounding system provides channels for the discharge of strong surge current caused

by lightning. If the sectional area of the grounding conductor is less than 150 mm2 [0.23 in.2],

keep the routing of the conductor as straight as possible.

CAUTION:

The grounding resistance must meet the local requirements. If there is no reference standard

for the resistance in the local area, the grounding resistance must be less than or equal to 10

ohms.

Figure4-7 shows the outdoor grounding system.

40


Figure4-7 Outdoor grounding of the building and steel tower

The outdoor grounding bar is generally installed at a place that is not more than 1 m [3.28 ft]

away from the feeder window. The grounding bar is connected to the earth electrode through

a black cable with a sectional area of more than 95 mm2 [0.147 in.2]. For details about the

installation of the outdoor grounding bar, refer to the instructions on the installation of the

indoor grounding bar.

Fastening the Grounding Clip of the Feeder

CAUTION:

When connecting the grounding cables to the grounding points such as the steel tower,

cable rack, and grounding bar, remove the anticorrosive paint on the contact part. After

connecting the grounding cables, coat the lug, nut, and grounding points using

anticorrosive paint and wrap the bare wire and the lug handle using an insulating tape.

When the grounding cables are grounded through the base of the grounding clip, the

installation of the base must meet the requirements mentioned above.

The requirements for the installation of the grounding clip are as follows:

When installing the grounding clip of the feeder on the steel tower,

41


If there is space for installing the grounding clip,

the grounding cables should be connected directly to the steel plate of the tower. In

this way, the tower can function as the conductor to discharge the surge current.

For details about the installation of the grounding clip of the feeder, refer to the

related instructions.

If there is no space for installing the grounding clip,

the base of the grounding clip should be located on the tower or the outdoor cable

rack, and the grounding cables should be connected to the base.

When installing the grounding clip on the roof of a building without a steel tower,

connect the clip to the grounding grid on the roof of a nearby building and ensure that

the grounding grid is grounded properly.

When installing the grounding clip on the outdoor cable rack,

connect the grounding cables properly to the grounded cable rack.

When leading feeders into the equipment room,

If the outdoor grounding bar is installed,

connect the grounding cables to the outdoor grounding bar and arrange the

grounding cables neatly. Connect the outdoor grounding bar to the grounding grid

by using the special conductor.

If the outdoor grounding bar is not installed,

connect the grounding cables properly to the grounded outdoor cable rack or to the

grounding grid of the building.

The connection points between the grounding cables and the grounding points

must be painted with anticorrosive paint.

4.2.5 Lightning Protection and Grounding of the Power Supply

System

This topic describes the lightning protection measures that should be taken for the power

supply system of the base station and the power cables.

Requirements for the Lightning Protection of the Power Supply System

The requirements for the lightning protection of the power supply system are as follows:

42


The DC working ground (reflow ground of the –48 V DC or +24 V DC power supply)

must be connected with the indoor grounding bar nearby. The grounding cable must

be capable of supporting the maximum load of the system.

The TN-S power supply system must be used in the event of AC power supply.

A dedicated power transformer must be used for the base station. Before the power

cables are connected to the base station, the cables must be covered by metal

jackets or steel tubes, buried under the ground (the buried section must be at least

15 m [49.21 ft.] long), and properly grounded.

When the power transformer is installed outside the equipment room, the following

requirements must be met:

For areas with more than 20 thunderstorm days every year and a ground

resistance greater than 100 ohm·m, install lightning protection cables for the

aerial cables. The length of the lightning protection cable must not be less than

500 m [1640.40 ft].

The angles formed between the power cables and the lightning protection

cables must be less than 25o.

All poles of the lightning protection cables (except for the last pole) must be

grounded independently.

NOTE:

A set of zinc oxide lightning arresters must be installed at the next to the last pole.

If the lightning protection cables for existing aerial power cables cannot be installed,

install the zinc oxide lightning arresters for each of the following poles of the aerial power

cables: the last pole, the last but one pole, the last but two or three pole, and the last but

four pole. In addition, install a set of high-voltage fuses for the last but three or four pole.

The lightning protection cable and the grounding body of the lightning arrester should be

of an outstretching or circle structure.

When the power transformer is installed inside the equipment room, the following


Lead the high-voltage power cables into the equipment room through

underground channels. The length of the power cables must not be less than

200 m [656.16 ft].

Install zinc oxide lightning arresters for the three phase lines that connect the

power cables and the aerial power cables. The metallic sheath of the power

cables should be grounded properly.

43


For the low-voltage power cables that are led into the equipment room, the following


Bury the cables under the ground before they enter the base station, and the

length of the cables should not be less than 15 m [49.2 ft]. If the high-voltage

side of the transformer uses power cables, the length of the low-voltage power

cables may vary based on the actual situation.

Install a lightning arrester at the place where the power cables connect the

AC power distribution panel. The neutral lines led out of the power distribution

panel need not be grounded.

For the three phase lines at the high-voltage side of the power transformer, the

following requirements must be met:

Install a set of zinc oxide lightning arresters near the phase lines.

Install seamless zinc oxide lightning arresters properly for the three phase

lines at the low-voltage side of the power transformer.

Ground the chassis of the power transformer, the neutral lines at the low-

voltage side, and the metallic sheath of the power cables connected with the

transformer properly.

Install lightning arresters at the place where cables run in or run out of the

base station.

Ground the uncharged parts of the power supply devices and the lightning arrester

properly. Do not conduct neutral protection.

Connect the DC working ground with the nearby indoor grounding bar.

The cross-sectional area of the grounding cables must range from 35 mm2

[0.054 in.2] to 95 mm2 [0.147 in.2] so that the cables are capable of supporting

the maximum load.

Use strand copper wires as grounding cables.

Equip the AC panel and rectifier (or high frequency switch power supply) with multi-

level protection devices.

The voltage withstanding capability of the lightning arresters must conform to the

relevant standards.

Requirements for the Lightning Protection of Led-In Power Cables

The requirements for the power cables led into the equipment room are as follows:

Install lightning arresters.

44


Do not lead AC or DC power cables into or out of the communications sites in an

overhead way.

After the low-voltage power cables are led into the AC rectifier and AC power

distribution box, the power cables must be equipped with a lightning arrester that is

grounded properly.

In rural areas, install a lightning arrester of which the current discharge

capacity must be equal to or greater than 40 kA.

In suburbs where thunderstorms occur relatively frequently, install a lightning

arrester of which the current discharge capacity must be greater than 40 kA.

In mountain areas that are prone to thunderstorms or in a high building that

stands alone, install a lightning arrester of which the current discharge capacity

must be greater than 100 kA.

The grounding cable of the lightning arrester must be less than 1 m [3.28 ft] in length

and greater than 25 mm2 [0.039 in.2]in cross-sectional area.


of Signal Cables

For the lighting protection of the signal cables, you can use shielded cables, installing

lightning arresters, or grounding the signal cables.

The requirements for the lightning protection of signal cables are as follows:

Do not route the signal cables in an overhead way.

Install lightning arresters at the place where the signal cables enter the base station.

Ground the idle lines in the signal cables properly.

Ground the ends of the metallic tubes that cover the outdoor signal cables properly.

Bury the signal cables under the ground before you lead the cables into the

equipment room or after you lead the cables out of the equipment room.

Ground the shielding layers securely before leading the signal cables into the

equipment room.

Ground the lightning arresters properly.

45


For areas that experience thunderstorms for more than 20 days every year and

where the ground resistance is greater than 100 ohm·m, take the following

measures during cable routing:

Route drainage wires over the signal cables.

Use the signal cables covered by metallic sheath.

Use optical fibers.

NOTE:

Huawei recommends that all signal cables use shielded cables.

Huawei recommends that lightning arresters be used for interconnection devices, so that

the protection against a differential mode of 3 kA or a common mode of 5 kA is achieved.


of Feeders

This topic describes the environment requirements of the satellite antennas and feeders.

Location Requirements of the Satellite Antennas

The location requirements of the satellite antennas are as follows:

The space between two antennas must be equal to or less than 1 m [3.28 ft].

The antennas should be located beyond the coverage of a directional antenna of

which the transmit power is greater than 1 W and the frequency is higher than 400 MHz.

In addition, the antennas should be located at least 20 m [62.62 ft] away from omni

antennas.

If possible, the antennas should be installed in the center of a roof. Do not install

them on the surrounding parapets or the corners of a roof.

If an antennas has to be installed on a parapet, the antenna should be preferably

installed at an area where it does not affect the aesthetics of the building and the feeder

can be fixed easily. In addition, the parapet should be strong so that it can be drilled for

mounting expansion bolts. A parapet of more than 600 mm [1.97 ft] in height is

recommended for mounting expansion bolts.

46


If an antenna has to be installed on a tower, the location of the antenna should be

higher than the top of the building where the equipment room is located. The antenna

should be kept far away from the high-power antenna on the top of the tower.

If a dedicated lightning rod is unavailable, lightning rods on the top of buildings or

towers work. In this case, you must consider the effect of interference.

The angle between the receiving end of the antenna and the lightning rod or the

angle between the connection line at the top of the tower and the vertical line must be

less than 45°. In areas prone to thunderstorms (more than 20 days every year), the

angle must be less than 30°. The horizontal distance between the antenna and the

lightning rod must be greater than 2 m [6.56 ft].

The upward vertical angle of the antenna should be greater than 90°, as shown in

Figure4-8.

Figure4-8 Location of the antenna

Location Requirements of the Feeders

The requirements for installing antennas are as follows:

When the antenna is installed on a roof, make sure that you route the feeder along

the root of the podium of the building roof and fix the feeder using a plastic clip with

steel nails. Arrange the tips of the plastic pieces alternately in opposite directions.

The space between the plastic pieces should be 1 m [3.28 ft]. All plastic pieces

should be aligned with the surface of the wall so that the cable reaches the cable

ladder on the roof. If the feeder is routed along the tower, use fixing clips to fix the

feeder.

47


When laying out a feeder, make sure that you expand the feeder first and avoid

bending it. If you have to bend it, ensure that the bending radius of the feeders

should be 20 times greater than the diameter of the feeder.

Use reliable material such as a packing bag to protect the connectors on both ends of

the feeder.

If there are two feeders, use temporary labels to identify them. You can write the

temporary labels in the same manner as the formal labels, or in any other manner.

Do not cross the feeders.

If the feeders are routed along a cable ladder, fix them using fixing clips with a space

of 2 m [6.56 ft].

The path from the building roof to the BSC room should be free of any obstacles. In

addition, waterproof and anticorrosion measures should be taken for the feeders.

Before leading the feeder indoors, bend the feeder to make a waterproof curve. The

vertical distance between the lowest part of the waterproof curve and the entrance

should be at least 200 mm [7.87 in.], to keep the rain water out of the room.

4.2.8 Requirements for Lightning Protection and Grounding of

Other Equipment

This topic describes the requirements for the lightning protection and grounding of other

equipment, such as the equipment room, metallic devices on the roof, bulbs on the roof, and

the cable rack.

The requirements for the lightning protection and grounding of the other equipment are as

follows:

The equipment room should be equipped with the devices, such as a lightning

protection band, lightning protection network, and lightning arrester. These devices

can protect the equipment from direct lightning strikes and inductive lightning

strikes.

All metallic devices on the roof of the equipment room should be connected with the

nearby lightning protection band.

The bulbs on the roof of the equipment room should be installed under the lightning

protection band.

If the power cables of the bulbs are routed through the tower or top of the building,

the cables must be enclosed in a metal tube.

48


The cable rack, steel shelf, rack or chassis, metallic air conduit, and metallic window

and door must be properly grounded.

The grounding cables are a bundle of copper wires with a cross-sectional area of

more than 25 mm2 [0.039 in.2].

4.3 Requirements for Transmission in the BSC

4.3.1 Physical Interfaces on the BSC

This topic describes the physical interfaces on the BSC.

Specifications of Data Transmission Ports

The BSC has external and internal ports for data transmission. The external ports are used

for data transmission over the Abis, A, and PCF interfaces. Table4-4 lists the specifications of the external transmission ports.

Table4-4 Specifications of the external transmission ports

Port Name Board Port

Type

Remarks

E1/T1 AEUBa DB44 This port is used for the ATM

transmission over the Abis

interface.

EIUAa DB44 This port is used for the TDM

transmission over the A interface.

PEUBa DB44 This port is used for the IP


interface.

PEUAa DB44 This port is used for the IP


Channelized

STM-1/OC3

OIUAa LC/PC This port is used for the TDM


49


Table4-4 Specifications of the external transmission ports

Port Name Board Port

Type

Remarks

AOUBa/AO1Ba LC/PC This port is used for the ATM


interface.

PO1Ba/POUBa/PO1Aa/

POUAa

LC/PC This port is used for the IP


interface and A interface.

FE/GE

electrical

port

FG1Ba/FG2Ba RJ45 This port is used for the IP


interface.

FG1Aa/FG2Aa RJ45 This port is used for the IP


FG1Pa/FG2Pa/FG1Xa/FG2Xa RJ45 This port is used for the IP

transmission over the PCF

interface.

GE optical

port

GOUPa/GOUXa LC/PC This port is used for the IP

transmission over the PCF

interface.

The internal transmission ports of the BSC are used for inter-subrack communication inside

the BSC. Table4-4 lists the specifications of the internal transmission ports.

Table4-5 Specifications of the internal transmission ports

Port Name Board Port Type Remarks

GE electrical port SCUOa RJ45 This port is used for the interconnection

between the CMPS and the CSPS inside

the BSC.

Specifications of the Clock Signal Ports and Satellite Signal Ports

Table4-6 lists the specifications of the clock signal ports and satellite signal ports.

50


Table4-6 Specifications of the clock signal ports and satellite signal ports

Port Type Board Port Port Type Remarks

GPS satellite

antenna port

ANT port on the panel

of the GCUOa

SMA male connector This port is used to

receive timing

information from the

GPS satellite system.

Clock signal

output port

CLKOUT port of the

GCUOa

RJ45 This port is used to

send 8 kHz and 1PPS

clock signals to the

SCUOa.

Clock signal

input port

CLKIN port of the

SCUOa

RJ45 This port is used to

receive 8 kHz and

1PPS clock signals

from the GCUOa.

CLKIN0 and CLKIN1

ports of the GCUOa

SMB male connector This port is used to

receive clock signals

from the BITS.

4.3.2 Peer Equipment and Interfaces Supported by the BSC

The BSC is connnected to the BTS, MSC, PDSN, and another BSC through the Abis, A1/A2,

A1p/A2p, A10/A11, and A3/A7 interfaces respectively.

4.3.3 Requirements for the PDF/DDF/ODF

If the BSC uses the PDF, DDF, or ODF, ensure that the PDF, DDF, or ODF meets the

associated requirements.

Requirements for the PDF

If the PDF is far from the BSC cabinet (for example, they are located in different equipment

rooms), the PGND cable of the BSC cabinet should be connected to the closest protection

51


grounding bar, that is, the cabinet is co-grounded with the PDF. For details about the routing

of the PGND cable, refer to the topic on the PGND cable of the PDF.

Requirements for the DDF

Prior to site deployment, a standard DDF should be arranged and installed by the customer.

The capacity of the DDF should meet the current demand and allow for future expansions. If

the capacity of the DDF is insufficient, Huawei recommends that a larger-capacity DDF

should be installed as soon as possible.

The connectors of the DDF should match the trunk cables. For details about the specifications

of the trunk cables, refer to the contract or contact design engineers. For the installation of the

DDF, copper cables with a cross-sectional area larger than 6 mm2 [0.0093 in.2] should be

used. The cables should be connected to the protection grounding bar in the equipment room.

Requirements for the ODF

The requirements for the ODF are as follows:

The optical ports of the ODF should be allocated following a top-down and left-right

sequence (facing outwards).

The metal case of the ODF and the internal wires of the optical cables should be

properly grounded.

For the installation of the ODF, copper cables with a cross-sectional area larger than

6 mm2 [0.0093 in.2] should be used. The cables should be connected to the

protection grounding bar in the equipment room.

4.4 Requirements for BSC Cable Layout

This topic describes the requirements for the layout of power cables, PGND cables, and

signal cables of the BSC.

4.4.1 Installation Specifications for Power Cables and PGND

Cables

The installation of power cables and PGND cables must meet the requirements for cable

layout and binding.

52


Requirements for Cable Layout

Before the layout of power cables and PGND cables, cable connectors should be

wrapped with insulating tape to avoid contact with PDF connecting terminals.

The layout of power cables and PGND cables should allow for future expansion.

Power cables and PGND cables should be routed separately from signal cables.

When power cables and PGND cables are parallel with signal cables, the spacing

between them should not be less than 10 mm [0.39 in.] inside the cabinet or less

than 100 mm [3.94 in.] outside the cabinet.

The bending radius of cables at turning should be five times larger than their

diameter.

During underfloor cabling, power cables should have an extra length at the cable inlet

of the PDB on top of the cabinet to ease insertion and removal. Power cables

should also be routed tidily.

When power cables are connected to the wiring terminals on the PDB in the cabinet,

they should be routed straight and bent smoothly at turning.

Requirements for Cable Binding

Power cables and PGND cables should be bound separately from signal cables.

Power cables and PGND cables should be bound at an interval of 200 mm [7.87 in.].

During underfloor cabling, power cables and PGND cables should be routed along

the column in the cabinet and bound to the wire bushing.

Cable ties of different types (100 mm [3.94 in.]/150 mm [5.91 in.]/300 mm [11.81 in.])

should be used depending on the number of cables.

Cable ties should face to the same direction.

The extra part of cable ties should be stripped off and all cuts should be smooth

without sharp projections. The cable ties indoors should be cut flush, and those

outdoors should have an extra length of 3 mm [0.12 in.] to 5 mm [0.2 in.].

4.4.2 Cabling Specifications for the BSC Signal Cables

This topic describes the cabling specifications for the BSC signal cables. The specifications

helps to ensure appropriate bending radius, neat routing, and appropriate binding of signal

cables.

53


Requirements for the Installation of BSC Signal Cables

If the connectors of the signal cables are made before delivery, pack the connectors

with soft and durable materials during the cabling to avoid damage.

Ensure that the jackets of the signal cables are not damaged during the cabling.

The actual installation positions of the signal cables must meet the requirements of

site survey and the data configuration.

When installing the optical cables, do not step on or stretch the optical cables.

Otherwise, the optical cables may be damaged.

Use dustproof caps to cover the optical connectors that are not in use.

When coiling extra optical fibers in the rear-mounted optical cable box, apply proper

force to avoid damaging the optical fibers.

Related operation guides describe the installation methods only. For the actual

installation positions of the cables, refer to the site survey requirements and the data

configuration plan.

When installing the signal cables, coil extra interconnection cables on the cable

ladder. Ensure that the bending radius meets the requirement.

Minimum Bending Radiuses of BSC Signal Cables

Table4-7 lists the requirements for the bending radii of BSC signal cables.

Table4-7 Minimum bending radii of signal cables

Cable Minimum Bending Radius

Ethernet cable 25 mm [0.98 in.]

Optical cable 40 mm [1.57 in.]

Trunk cable 40 mm [1.57 in.]

Requirements for the Routing of BSC Signal Cables

Separate the signal cables from the power cables. If the signal cables cross the

power cables, the angle must be 90°.

Ensure that the requirements for the bending radii of signal cables listed in Table4-7

are met.

54


Reserve extra lengths of signal cables near connectors for the convenience of

inserting and pulling the connectors.

Do not cross the signal cables over each other when routing the signal cables inside

the cabinet. The signal cables shall be led out along the two sides of the subrack.

Arrange the cables of which the connectors are far away from the ports on the external

side of the cable bundle and other cables on the internal side of the cable bundle. The

cables must not cross each other, and they should routed neatly without any tangling.

When the signal cables are routed on the cable ladder and the distance between the

cable ladder and the top of the cabinet exceeds 800 mm [2.62 ft], use a ladder to lead

the signal cables downwards.

Lead the signal cables into or out of the cabinet through the cable holes, as shown in

Figure4-9. Before routing, remove the plastic rodent-proof nets from the cable holes.

After routing, cut appropriate plastic rodent-proof cover plates, cover the cable holes in

the upper and lower enclosures, and use screws to fix the cover plates.

Figure4-9 Cable holes

Figure4-10, Figure4-11, and Figure4-12 how to route trunk cables.

55


Figure4-10 Routing and binding trunk cables on the cable ladder

Figure4-11 Routing trunk cables upwards along the cable ladder

56


(1) Cable ladder (2) Trunk cable (3) Cable tie

Figure4-12 Routing signal cables from the cabinet to the cable ladder

The cabling should be neat, appropriate, and in accordance with the engineering

design.

The cabling should be clear, proper, and smooth at the bends. The cables are laid in

parallel.

The cabling should facilitate future maintenance and capacity expansion.

Requirements for the Binding of BSC Signal Cables

Bind signal cables separately from power cables. When signal cables are laid parallel

to power cables, leave a minimum distance of 10 mm [0.39 in.] between signal cables

and power cables inside the cabinet and a minimum distance of 100 mm [3.94 in.]

between them outside the cabinet.

If twines are used for the binding, wax the twines in advance.

Bind the signal cables at the entrance and the exit of the cable trough and at the

bends, as shown in Figure4-13. Do not bind the signal cables in the cable trough.

57


Figure4-13 Binding signal cables

Bind optical cables in pairs at intervals of 150 mm [5.91 in.]. Cover the optical cables

outside the cabinet by using corrugated pipes.

Bind the cables that are routed on the cable rack and bundle them neatly.

Reserve extra lengths of the signal cables near connectors for the convenience of

inserting and pulling the connectors.

Point the tips of the cable ties to the same direction, and bind the signal cables with

proper tightness. For indoor cable ties, cut off the surplus part completely. For

outdoor cable ties, leave an extra length of 3 mm [0.12 in.] to 5 mm [0.20 in.].

Arrange the cable ties evenly. For the trunk cables outside the cabinet, it is

recommended to bind them at an interval of 1,000 mm [3.28 ft]. For the trunk cables

inside the cabinet, it is recommended to bind them at an interval of 150 mm [5.91

in.] to 200 mm [7.87 in.]. For Ethernet cables, it is recommended to bind them at an

interval of 70±5 mm [2.56 in. to 2.95 in.].

4.5 Requirements for the Clock of the BSC

This topic describes the requirements for the clock resources of the BSC.

4.5.1 Clock Resources of the BSC

The clock resources of the BSC are BITS clock signals, line clock signals extracted from the

A interface, satellite synchronization clock signals, and board free-run clock signals.

58


BITS Clock Signals

The BITS clock signal is obtained by the BSC from the BITS clock device. There are three

types of BITS clock signal: 2 MHz clock signal, 2 Mbit/s clock signal, and 1.5 Mbit/s clock

signal. The BITS clock signal has two input modes: BITS1 and BITS2. The BSC obtains the

clock signal through the clock input port on the GCUOa.

NOTE:

The 2 MHz clock signal and 2 Mbit/s clock signal are E1 clock signals. The 1.5 Mbit/s

clock signal is a T1 clock signal.

BITS1 and BITS2 maps to the CKLIN0 port and the CLKIN1 port on the GCUOa

respectively.

Line Clock Signals

The 2.048 MHz line clock signals extracted by the EIUAa, OIUAa, PEUAa, POUAa, or

POU1Aa from the A interface are used as the clock reference source of the

GPS Satellite Synchronization Clock Signal

The GPS satellite synchronization clock signal is 1 pulse per second (PPS) signal extracted

by the BSC from the GPS satellite system. The BSC can receive clock signals from the GPS

satellite system through the satellite antenna port on the GCUOa.

Board Free-Run Clock Signals

When BITS clock source and line clock source are unavailable, the BSC can use board free-

run clock signals.

4.5.2 Requirements for Clock Precision of the BSC

The specifications of the BSC clock signals are the clock precision, the pull-in range, the

maximum frequency offset, and the maximum initial frequency offset.

Table4-8 lists the requirements for clock precision.

59


Table4-8 Requirements for clock precision

Item Specification

Clock precision ±4.6×10-6

Pull-in range ±4.6×10-6

Maximum frequency offset 2×10-8 per day

Maximum initial frequency offset 1×10-8

60


Chapter5 Checklist for BSC Site

Preparation

5.1 Checklist for the Site Location

Item Requirements Specifications Result

Site

location

Keep the site away from the environments with high

temperature, poisonous gases, flammable or

explosive objects, electromagnetic interference

(radar station, radio station, and electric substation),

and unstable voltage.

Good

The site must be located away from pollution

sources, such as frequent earthquakes and strong

noise. While designing the project, consider

hydrographic, geological, seismic, power supply, and

transportation factors. Select a site that meets the

engineering and environmental requirements for the

telecom equipment.

Good

The site should not be located in an area that is near

the sea. The minimum distance from the seaside is

500 m [0.31 miles].

Good

The site must be located away from water bodies.

For example, the site should be located at a place

that is higher than the sea level.

Good

61


5.2 Checklist for the Equipment Room Environment


Height Minimum height under the

beam

3 m [9.84 ft] to 3.5 m [11.48 ft]

Bearing

capacity

Bearing capacity of the

floor

Not lower than 450 kg/m2 [0.64

bf/in.2]

Wall Wallpaper or lusterless

paint

Difficult to be chalked

Floor ESD floor Semiconductor and dustless

Door and

window

The door is 2 m [6.56 ft]

high and 1 m [3.28 ft]

wide. One door panel is

enough.

Doors and windows are sealed with

dustproof plastic tape. Double-layer

glass is recommended for windows.

Groove in

the room

The groove is used for

routing various cables.

The inner side should be smooth

and conform to the requirements for

the transmission equipment layout.

Temperatur

e

Long-term working

temperature

0℃ to 45℃

Short-term working

temperature

-5℃ to +55℃

Humidity Long-term working

humidity

5% to 85%

Short-term working

humidity

5% to 95%

Anti-EMI Electric field Not more than 300 mV/m

Magnetic field Less than 11 Gs

ESD ESD floor The volume resistivity should be 1.0

62



protection x 107 ohms to 1.0 x 1010 ohms.

5.3 Checklist for the Power Supply System

NOTE:

Before checking the power supply system, ensure that the cabinet is grounded.


Voltage of the DC

power supply

The primary power

supply and the

storage battery work

in the mutual hot

backup mode.

The voltage ranges

from -57 V DC to -

40 V DC.

Standby generator A standby generator

is recommended.

Good

Voltage of the AC

power supply

187 V AC to 242 V

AC

Good

Routing of power

cables

The –48 V power

cables should be led

to the power

distribution cabinet

or power distribution

box.

Good

Alarms for power

supply

Alarms are

generated when the

power supply is

disconnected or

faulty.

Good

63


5.4 Checklist for the Grounding Cables


Main grounding bar

and branch

grounding bar

The distance between the copper

bar and the copper wires should

be as short as possible. The

grounding cables should be as

thick as possible.

The installation is

complete and the

grounding cables are

in good contact.

Grounding resistance Integrated grounding The grounding

resistance is less than

or equal to 10 ohms.

Grounding cable

entrance

The grounding cables should be

led to the power distribution

cabinet or power distribution box.

Good

5.5 Checklist for the Transmission System


Trunk cables The trunk cables should not be arranged overhead.

If the trunk cables have to be arranged overhead,

they should have double shielding layers or metallic

sheath. The shielding layers or metallic sheath

should be securely connected to the grounding

bars.

Good

ODF The optical transmission system is ready for use.

The ODF or fiber distribution box is installed.

Optical fibers are interconnected.

Good

Transmission

system

The transmission system should be already tested

and meet the engineering requirements.

Good

64


Chapter6 Physical and Electrical

Parameters of CDMA BSC

Switching Equipment

6.1 Structure Specifications

Item Specification

Cabinet specifications The structure design complies with the IEC 60297 standard

and the IEEE standard.

Dimensions of the N68E-22

cabinet

2200 mm [86.61 in.] x 600 mm [23.62 in.] x 800 mm [31.50

in.]

Dimensions of the N68-21-N

cabinet

2133 mm [83.98 in.] x 600 mm [23.62 in.] x 800 mm [31.50

in.]

Available clearance inside the

N68E-22 cabinet

46 U

Available clearance inside the

N68-21-N cabinet

44 U

Weight of the N68E-22 cabinet Fully configured cabinet: ≤ 350 kg [771.60 lb]; empty

cabinet: ≤ 140 kg [308.64 lb]

Weight of the N68-21-N

cabinet

Fully configured cabinet: ≤ 410 kg [903.88 lb]; empty

cabinet: ≤ 170 kg [374.78 lb]

65


6.2 Electrical Specifications

Item Specification

Lightning

protection

±4000 V, 8/20 μs

Working voltage DC power supply: –48 V DC

Range: –40 V DC to –57 V DC

Power

consumption

Power consumption of the entire cabinet: ≤ 8200 W

6.3 Specifications for GPS feeders and jumpers

Distance Between the Satellite Antenna

and the Main Devices

Specifications for GPS Feeders and

Jumpers

< 100 m [328.08 ft.] 1/2'' jumper

100 m [328.08 ft.] ≥ L (the length) < 300 m

[984.25 ft.]

7/8'' feeder

≥ 300 m 5/4'' feeder

66


Chapter7 Physical and Electrical

Parameters of M2000 OMC

Equipment

Equipment

Type

Equipment

name

Physical specifications

(single cabinet)

Electrical specifications (single

cabinet)

Dimensions

(mm)

(WidthDept

hHeight)

Weight

(kg)

Current

(A)

Voltage

(V)

Power

consumption

(W)

(Fully

equipped)

M2000Server

cabinet

610 930

1870

159

(empty

cabinet)

10220 - 240V

AC

600 800

2100300 10 -48V DC

Alarm boxGM12 alarm

box

400 100

280/ 0.75

-48V DC or

220V AC40

M2000

maintenance

equipment

ClientAs large as a

PC/ 1.36 220V AC <400

Alarm

console

As large as

a PC/ 1.36 220V AC < 400

Dialup

server

As large as

a PC/ 2.27 220V AC 500

M2000 server Sun server

E4500

340 500

56068 12

100 -

240V AC1400

Sun server

Blade 1000

256 610

455

31.8 4 100 -

120V AC

220 -

390

A maximum of

875 W

67


240V AC

Sun server

Netral 1405

(dual

nodes)

/ 220V AC 1600

Router

Cisco3640 445 400 87 13.6 –100 - 240V

AC140

Quidway25

01

445 268

445 1.5

100 -

240V AC20

Quidway26

31

442 210

458 –

85 -

264V AC70

LAN switch

Catalist2950 /100 - 240V

AC35

Quidway30

26

436 338

43.54 –

90 -

264V AC60

Timeslot

cross-connect

equipment

Mercury36

00

430 330

443 –

90 -

240V AC35

68

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Preparation Guide to CDMA2000 BSC6680 Engineering Installation

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