Load calculation on existing panel

[homwire]

How would someone calculate total load on existing residential panel? I have a 60A sub panel keep tripping. It did not trip on any breakers in the sub panel but on the 60A breaker in the main panel. I am wondering if the 60A breaker is overloaded.

Would like to hear any thoughts from anyone. Thanks.

 

[Smart $]

How would someone calculate total load on existing residential panel? I have a 60A sub panel keep tripping. It did not trip on any breakers in the sub panel but on the 60A breaker in the main panel. I am wondering if the 60A breaker is overloaded.

Would like to hear any thoughts from anyone. Thanks.

Calculating load is spelled out in Article 220. Fairly straightforward, but not really a great tool for troubleshooting. The best method... at least more suitable... is to amp clamp the feeder and note current levels with everything turned on. Some speculation may be necessary for intermittent loads if you can't force them all to be on or start at the same time.

 

[homwire]

Will try to identify every circuits in the panel then calculate according to Code. But by measuring it will also works. I just didn't think of it before you pointed it out. Thanks.