Document: NUREG-0800
Document ID: 98a045ec-37ef-46fc-9eaa-9e695c2d6e53
Document Type: srp
Title: OFFSITE POWER SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350488.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.2
CFR Part: 
CFR Title: 

Content:
through the generator circuit breaker. The fault current interrupting capabiltiy (short circuit current rating) of the circuit breaker should be demonstrated by performing a series of tests similar to those called for in ANSI C37.04 and C37.09. The tests should include close/open (CO) operations and should be performed at the circuit breaker minimum rated air pressure and control voltage and with a rate of rise of recovery voltage not less than the following rated value. d. Maximum Rate of Rise of Recovery Voltage The rated maximum rate of rise of recovery voltage (RRRV) of the circuit breaker should not be less than the maximum RRRV imposed on the breaker in the circuit in which it is used. e. Short-Time Current Carrying Capability The circuit breaker should have the capability of carrying a fault current for the length of time that the fault exists assuming failure of the primary protective device to clear it. The fault current chosen should be that due to a fault on the system at a point which causes the largest 12t heating of the circuit breaker. The short-time current carrying capability should be demonstrated with a current carrying test. f. Momentary Current Carrying Capability The circuit breaker should have the capability of carrying the maximum crest value of current calculated for the worst case bolted three phase fault on the system. This capability should be demon- strated by test. 8.2-312 Rev. 0 - July 1983 g. Transformer Magnetizing Current Interruption The circuit breaker interruption of an unloaded station main and/or auxiliary transformer magnetizing current should not generate excessively high surge voltages which could damage the connected bus and transformer insulation. This should be verified by test. h. Thermal Capability The thermal capability of the circuit breaker should be demon- strated by a test at its continuous current rating. The test should be in accordance with the requirements and ratings contained in ANSI C37.04 and C37.09. For