Testing Short Time Pickup 1

[artvandelayb4u]

I am looking for advice on a methode for Primary Injection testing Short Time pickup on LV Power Circuit Breakers. I am well informed on all other Primary Injections tests on Circuit Breakers, including short time delay, but am having a hard time finding information on short time pickup.

 

[DTR2011]

I would say that depends on the test equipment you have available and the trip units you are testing.

If you have some kind of modern test set, where you can control the pulse length, set the fault time to be longer than the STD, but a lower magnitude than the INST PU. Ramp up into the STPU level. Assuming the trip unit has some kind of LED for ST PU, that is an indication.

Most of the rest of it is similar to other primary tests