MMC GAMUDA KVMRT (T) SDN. BHD. PROJEK MASS RAPID TRANSIT LEMBAH KLANG UNDERGROUND WORKS (TUNNELS, STATIONS & ASSOCIATED STRUCTURES) BETWEEN SEMANTAN NORTH PORTAL AND MALURI SOUTH NORTAL DESIGN CHANGE NOTICE (DCN) DCN Ref.: DCN/ALL UG1/M&E/004 To : David Parks(CRE) Company : Aecom – Mott Macdonald JV TQ Ref : Revised drawing required : No Yes, By ____Next SEM Submission___(Target date Existing Condition : Related to incoming termination method for tunnel ventilation system (TVS) motor control centre (MCC) panel. Current design philosophy is based on:- Outgoing – direct feed from LV switchboard complete with MCCB rated to discrimination Incoming – direct feed from LV switchboard complete with isolating switch Reason for Change : Following MRTC’s instruction of replacing isolating switch at TVS MCC panel incoming for all UG 1 stations and tunnel ancillary buildings where TVS applies. MRTC comments received Jan 2015. No such comment received in previous discussion and Drawing Numbers (and/or Design Documents) affected by the proposed change: TVS MCC Schematics require to be updated for the following areas:- - North Portal - Intervention Shaft 01 - Intervention Shaft 02 - KL Sentral Museum Negara Station - Pasar Seni Station - Merdeka Station - Bukit Bintang Station MMC Gamuda KVMRT (T) Joint Venture KVMRT/MG/SBK/UG/OP/MSP/DCP/0027, Rev. 04
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MMC GAMUDA KVMRT (T) SDN. BHD.PROJEK MASS RAPID TRANSIT LEMBAH KLANG UNDERGROUND WORKS
(TUNNELS, STATIONS & ASSOCIATED STRUCTURES) BETWEEN SEMANTAN NORTH PORTAL AND MALURI SOUTH NORTAL
DESIGN CHANGE NOTICE (DCN)
DCN Ref.: DCN/ALL UG1/M&E/004
To : David Parks(CRE)Company : Aecom – Mott Macdonald JVTQ Ref :Revised drawing required : No Yes, By ____Next SEM Submission___(Target date of revise drawing)
Existing Condition :
Related to incoming termination method for tunnel ventilation system (TVS) motor control centre (MCC) panel.
Current design philosophy is based on:-Outgoing – direct feed from LV switchboard complete with MCCB rated to discriminationIncoming – direct feed from LV switchboard complete with isolating switch
Reason for Change :
Following MRTC’s instruction of replacing isolating switch at TVS MCC panel incoming for all UG 1 stations and tunnel ancillary buildings where TVS applies.
MRTC comments received Jan 2015. No such comment received in previous discussion and workshops.
Drawing Numbers (and/or Design Documents) affected by the proposed change:
TVS MCC Schematics require to be updated for the following areas:-- North Portal- Intervention Shaft 01- Intervention Shaft 02- KL Sentral Museum Negara Station- Pasar Seni Station- Merdeka Station- Bukit Bintang Station
MMC GAMUDA KVMRT (T) SDN. BHD.PROJEK MASS RAPID TRANSIT LEMBAH KLANG UNDERGROUND WORKS
(TUNNELS, STATIONS & ASSOCIATED STRUCTURES) BETWEEN SEMANTAN NORTH PORTAL AND MALURI SOUTH NORTAL
Description Of Change : (please attach details, if any)
[1)] To provide the equivalent MCCB/MCB at the incoming of all TVS MCC panel to the corresponding outgoing MCCB/MCB at the LV switch panel
[2)] No discrimination between incoming of TVS MCC panel and outgoing of MSB required to standardize with elevated stations.is considered as the fault is related to the same connecting cables therefore it is either upstream or downstream will terminate the electrical power supply.MCCB/MCB requested at the incoming of TVS MCC panels are for maintenance purpose only as per MRTC comment received in Jan 2015.
Changing isolator to MCCB at incomer doesn't facilitate maintenance
MMC GAMUDA KVMRT (T) SDN. BHD.PROJEK MASS RAPID TRANSIT LEMBAH KLANG UNDERGROUND WORKS
(TUNNELS, STATIONS & ASSOCIATED STRUCTURES) BETWEEN SEMANTAN NORTH PORTAL AND MALURI SOUTH NORTAL
Tunnel Ventilation System - KVMRT_MG_SBK_UG1_STN018A_ME_TV_SCM_0002_W00
This shows outgoing to TVS MCC Panel, c/w MCCB
The circled incoming isolating switch (current) to be replaced with equivalent rating MCCB as per the outgoing of the corresponding power supply from LV switchboard.
