| There aren't very many labs left in the world that can do the type of | testing you are talking about. Our lab in Lenox MA |
| only does up to 10,000A surges. I think BC Hydro may still have a lab that | can test at 100 kA. I know of a couple of European labs and perhaps a | couple of Asian labs that can perform that kind of testing. Many utilities | used to have those kinds of labs, but sadly most have completely abandoned | their labs and the few that remain have retired their higher current | equipment. I run our low voltage lab |
) and we can do | a few thousand amps if we really need to. | | It just hasn't been economical for utilities/companies to maintain those | kinds of testing capabilities, with the exception of breaker manufacturers. | It is certainly not something you are going to want to try to build on your | own.
I'm not interested in trying to build such a test lab. But I am curious what goes into the making of one. What would breaker manufacturers like Cutler-Hammer, GE, Siemens, and Square-D use to test their 600 volt class breakers? And what would UL use to indepedently verify the interruption ratings?
And then there are test procedures. How many units would need to be tested for valid sampling? How many tests would have to be performed on a single unit? Would the test involve closing a bolted fault on the load side of an energized and closed breaker? Would that test be limited to a cold breaker, or would it be applied to a breaker running full rated current and voltage for a few hours? Would the test involve closing the breaker onto an already bolted fault? Would the test involve energizing a breaker already closed onto a bolted fault? Would power factors less than unity be tested at fault current levels? Would every combination of phase faulting be tested?
What kinds of testing would be appropriate for a newly constructed home to verify that the electrical work meets specifications (and not just passes inspection)? If I have 200 amp service and a 200 amp main breaker, I should expect that if I run test loads above 200 amps I should have a main trip within certain times at certain current levels based on the manufacturer trip curves. At what point could such testing risk damaging the system?