Jump to latest postDoes anyone have a standard for high current testing breakers ,I have not seen anything from NETA
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Does anyone have a standard for high current testing breakers ,I have not seen anything from NETA
NETA Level III
Posted June 14, 2015
Pro Subscriber
what kind of standard are you looking for? I have some manufacturers field testing manuals that cover primary injection testing.
Long time is %300 or %600. There is nothing for short time and instantaneous is 10 times breaker rating ground fault is questionable
NETA Level III
Posted June 14, 2015
Pro Subscriber
I was able to find a section from a Square D Field Maintenance Guide for electronic trip circuit breakers that covers performance testing. Looks like this might be what you are looking for, it has procedures for Long Time, Short Time, Instantaneous and Ground Fault as well as Insulation Resistance and Contact Resistance tests. See the document attached to this post. Hope this helps.
NETA Level III
Posted June 14, 2015
Pro Subscriber
Looks like long time is 300%, short time delay and ground fault are 150%, according to Square D. For instantaneous start at 70% of expected trip value and apply 10-cycle pulses as you raise current.
Are they saying that %150 for short time and ground fault is what calculation is it % 150 of what
NETA Level III
Posted June 14, 2015
Pro Subscriber
150% of the determined pickup value. All dependent on your trip settings at time of test.
Originally Posted by Larry5443
Can you explain with a formula please
NETA Level III
Posted June 14, 2015
Pro Subscriber
Here is a quick example: If you had a 1000A circuit breaker with a short time pickup of 3X it should trip on short time around 3000A. You would first verify that by turning off I2t (if applicable) and ramp up current starting from about 2500A, the breaker should trip around 3000A. Next, turn I2t back on (if applicable) and preset your current to 150% of the pickup value (in this case: 3000A x 1.5 = 4500A). Initate current at that value and the breaker should trip within its specified time.
Give that PDF a read, it is all explained in there stp by step.
I understand what you are saying ,Iam asking is there anything that is written as far as a standard from Neta or anyone else in the testing organization .
