ECN Forum Forums General Topics of the Trade General Discussion Area POP sound in panel what is it?

ITE-Bulldog-

60's vintage- here in NewEngland.
Still plenty around and holding up impressively.
Rugged little system. I have several of the breakers in stock for the occasional fail.
The big ones- 100A mains,30-50 A 2 poles.
Just for the emergency replacements.
Never heard one 'POP' tho.