Testing of Medium-Voltage Circuit Breakers

[CuriousElectron]

Greetings,
Per IEEE 37-013, manufacturer of HV CBs are required to perform extensive numbers of tests, including short-circuit test, withstand test, etc. How are they able to comply with the standard/spec, and demonstrate that their products meet those requirements considering the high magnitude of rated and fault current amperage values they need to generate in order to perform these tests??
Thanks,
EE

 

[LionelHutz]

Rated current is relatively easy. A 3-phase variac and a step down transformer can do thousands of amps at a few volts.

There are test labs that can generate the necessary fault current levels for those tests.

 

[bacon4life]

Test labs have a variety of tricks. Some tests involve switching be one source that can produce high voltages at low currents to a source that produces high currents at low voltages. Other tricks involve various capacitor bank energy storage techniques.

Often the procedure is not intending to reproduce all real world behavior in a single test. Instead, several different tests are performed, and then the results are combine mathematically into a rating.

 

[thermionic1]

There's a video on the page attached that goes through testing

https://www.eaton.com/us/en-us/services/high-power-test-labs/franksville-high-power-lab.html