Yes it is cheaper to replace than test. But the circuit breakers that are found not to trip would be my concern. Having tested thousands of these small circuit breakers it is interesting on the number that just simply fail to trip (thermal or magnetic). In my experience, the failures seem to...
IEM, in Fremont, CA, can build a custom enclosure. They can also supply you with custom busbars, if needed. Plus it is local to you if you are indeed based out of Santa Cruz.
It is possible that the current standards no longer recommend the sizes for testing. I have seen older NFPA 70B documents stating 400A and above, but that looks to have been removed from the current version. By not recommending a size to test, the standard writers distance themselves should a...
Neutral to ground bonding can effect the proper functioning of ground fault protection schemes. Improper placement can create objectionable current or bypass the protection CT's.
Also you may require an additional neutral to case bond for the transformer.
A good review of NEC Article 250 could...
Forgot to mention, typically during the Doble excitation test the measurements will be in mA and Watts. But every situation is different.
The factory results are not to be considered for comparison, there is a published whitepaper dealing with that.
Look for a copy of Doble Test Procedures...
Something is not right. Usually when it is me testing and I get results like that, I probably did something wrong. Connections or wrong programming of test equipment.
Tested following standard Doble procedures? Forgive me for assuming the test set used was Doble M4000.
Post indicates tested at...
