To prescribe the rules for planned removal and restoration of the 1500V supply in the Network.
Only Network Controllers may give clearance for the removal of 1500V supply.
The 1500V supply must be removed only:
- if all prescribed approvals have been obtained, and
- in accordance with the requirements specified in the Maintenance Representative’s Electrical Safety Instructions.
For planned removal in Electric Vehicle Maintenance Centres (EVMCs), see NGE 226 Planned removal of the 1500V supply in Electric Vehicle Maintenance Centres.
For unplanned removal, see NGE 228 Unplanned removal of the 1500V supply.
Advertising 1500V supply removal
Planned removal of 1500V supply must be advertised.
Removal of the 1500V supply from an overhead wiring section must be authorised or notified using an Authority for Removal of Supply from 1500 Volt Sections form.
Clearance to remove the 1500V supply
The Electrical System Operator must get clearance from the relevant Network Controller before removing the 1500V supply.
The Network Controller must record, in permanent form, the details about the planned removal of the 1500V supply before giving the clearance.
If the removal of the 1500V supply affects more than one Network Controller area, the Network Controllers for the affected area must confer and nominate a Coordinating Network Controller.
The Coordinating Network Controller must:
- give the clearance to the Electrical System Operator, and
- record, in permanent form, the details about the planned removal of the 1500V supply.
If a signal box needs to be switched in after the clearance to remove the 1500V supply has been given, the Network Controller must tell the Signaller the details about the removal of the 1500V supply.
Applying blocking facilities
Signallers must prevent rail traffic from entering the isolated 1500V overhead wiring sections by:
- setting signals at STOP, and
- applying blocking facilities in accordance with NSG 614 Blocking facilities, and
- making sure that protection has been applied to prevent entry by way of unsignalled routes.
If it bridges isolated and live 1500V overhead wiring sections, a raised pantograph will re-energise an isolated section.
Travel between live and isolated sections
Electric trains or electric locomotives must not enter or leave an isolated 1500V overhead wiring section unless:
- their pantographs have been lowered with the air supply isolated, and
- they are hauled by diesel locomotives.
If the motive power of approaching rail traffic is not known, before the train may enter an isolated 1500V overhead wiring section, the relevant Signaller must:
- stop the rail traffic, and
- determine its motive power, and
- tell the Network Controller if rail traffic requires electric traction.
Restoring 1500V supply
The 1500V supply must be restored in accordance with the requirements specified in the Maintenance Representative’s Electrical Safety Instructions.
When the 1500V supply has been restored, the Electrical System Operator must tell affected Network Controllers.
Removing blocking facilities
If they are not needed to protect other work in the affected 1500V overhead wiring sections, Signallers must:
- remove blocking facilities, and
- tell Network Controllers.