Section Cover Page Section 16143 2000-06-01 Ground Fault Protection

This Master Specification Section contains:

.1 This Cover Sheet

.2 Specification Section Text:

1. General 1.1 Related Requirements 1.2 Related Work Specified In Other Sections 1.3 System

2. Products 2.1 Components

3. Execution 3.1 Transformer Protection 3.2 Relay Mounting On Transformers

BMS Basic Master Specification Alberta Infrastructure Page 0 Master Specification System Section 16143 Plan No: Ground Fault Protection Project ID: Page 1

1. General

1.1 RELATED REQUIREMENTS

.1 General Electrical Requirements: Section 16010.

1.2 RELATED WORK SPECIFIED IN OTHER SECTIONS

.1 Service and distribution: Section [ ] .2 Controls and instrumentation: Section [ ]

1.3 SYSTEM

.1 Provide line to ground fault protection system consisting of current transformers and adjustable ground fault relays.

.2 Develop time bands, pick-up points and time settings of the ground fault relays as part of the overall coordination scheme provided by the switchgear supplier.

2. Products

2.1 COMPONENTS

.1 Provide sequence current transformer wrapping and 3 phase and/or 3 phases and neutral conductors, consisting of rectangular window type for buses or circular types of cable.

.2 Connect secondary of the current transformers to an adjustable ground fault relay and to the breaker shunt trip.

.3 Provide ground fault relays with a minimum of three adjustable pick-up points and four time band settings, mounted in flush drawout case, complete with indication to indicate if breaker tripped on over current or on ground fault.

.4 Provide pilot light to indicate when system is energized.

3. Execution

3.1 TRANSFORMER PROTECTION

.1 Connect the transformer secondary to ground fault sensing relay for connection to the shunt trip coil of primary feeder [breaker] [distribution switch].

.2 Incorporate feature on secondary of transformer to facilitate the testing of the calibration of ground fault relays. Section 16143 Plan No: Ground Fault Protection Project ID: Page 2

3.2 RELAY MOUNTING ON TRANSFORMERS

.1 Mount ground fault relays associated with the transformers secondary ground straps in surface mounting enclosure external to the transformer case.

.2 Mount ground strap current transformers either within the transformer enclosure, or in a suitable sized pullbox containing the transformer's secondary ground strap; where practical, combined with relay enclosure.

END OF SECTION