NEMA SG 4
NEMA SG 4 2009-JAN-01 Alternatng-Current Hgh-Voltage Crcut Breakers
This standards publication encompasses:
a. All ratings for outdoor circuit breakers above 1000 volts for alternating-current service. (Automatic circuit reclosers are excluded.) Circuit breakers for service in metal-clad enclosures are included in NEMA Standard SG 5.
b. Attachments for these circuit breakers, such as bushing current transformers, bushing potential devices, interlocks, undervoltage trip devices, shunt trips, overcurrent trips, and auxiliaries sold with the circuit breakers such as closing relays and structural steel supports.
c. Renewal, modernizing, and spare parts for these circuit breakers and attachments.
d. Recommended installation, operation, and maintenance procedures.
Customers who purchased NEMA SG 4