Webster Substation, Franklin, NH
115kV Electrical and P&C Modifications
Project Scope Included: Replacement of aging circuit breakers concurrently with other obsolete equipment specified within several transmission project summaries; and replacement of 115kV switches, potential devices, CCVTs, LAs, cap and pin insulators, and protection and control relays in the Webster Substation. Work required detailed coordination, with phased project drawings for (3) outages, and costs allocated to (5) specific work orders.
Further scope included:
- Removal and replacement of (1) 115 kV M127 circuit breaker and (4) bushing potential devices, (2) 115kV manual gang operated disconnect switches, conductors, cables and connectors drops, and removal and replacement of CT wiring in the breaker panel and aux relays, as required.
- Removal and replacement of (1) 115kV L176 circuit breaker, (2) manual disconnect switches, installation of (1) 115kV Bus 5 CCVT with stand and foundation, conductors, cables and connectors, and removal and replacement of CT wiring in the breaker panel and aux relays, as required.
- Removal and replacement of an L176 115kV breaker failure and reclosing relay, directional over-current, timing and reclosing relays and other associated devices and equipment, and modification of the breaker panel.
- Removal of the existing L176 obsolete secondary line protection distance and over-current relays and associated obsolete test switches, lockout relays and metering devices, installation of (1) new GE D60 relay, test switches, aux relays, terminal blocks for the proper functioning of the secondary protection scheme, and modification of the breaker panel.
- Replacement of obsolete tandem under-hung manual disconnect switches, bypass switches, line switches, bus tie switches, LAs, CCVTs, and drops. Installation of (2) 115kV 2000A manual tandem gang operated, under-hung disconnect switches, line switch with rigid bus, (1) gang operated 2,000A bus tie switch, rigid bus/conductor, connectors, insulators, and conduit and cables, as required.