The attached photo was taken after an electrician went to the hospital with 2nd degree burns. This 400 amp CB tripped he was called out to check why the CB tripped he could find no problems (he did not megger anything).
Upon resetting the CB he got burnt and tripped the GFP.
We were called to check out the problem. Upon arriving I megged the line and load both were a dead short. I removed the cover of the CB this is what I found.
Two things, UPON instantaneous operation of ANY CB the CB must be inspected and or meggered and should be micro-ohmed (measure contact resistance).
NEVER close any CB that has operated till the source of the fault or overload has been located.
Upon resetting the CB he got burnt and tripped the GFP.
We were called to check out the problem. Upon arriving I megged the line and load both were a dead short. I removed the cover of the CB this is what I found.
Two things, UPON instantaneous operation of ANY CB the CB must be inspected and or meggered and should be micro-ohmed (measure contact resistance).
NEVER close any CB that has operated till the source of the fault or overload has been located.