A faulty MCCB by any chance?
I can't think of many other things, as a 125A MCCB even set to 0.6 on the thermal setting would still be 75A to trip, and you're obviously not getting anything like that....
Have you tried a data logger or current clamp with a peak hold setting to see whether there is anything untowards?
I can't think of many other things, as a 125A MCCB even set to 0.6 on the thermal setting would still be 75A to trip, and you're obviously not getting anything like that....
Have you tried a data logger or current clamp with a peak hold setting to see whether there is anything untowards?