ECN Forum Forums General Topics of the Trade General Discussion Area Odd Circuit Breaker Behavior

Could be one, or more, of the following:

<OL TYPE=A>

[*] Fuse was Non-Time Delay type (Fast Acting),


[*] Terminations at the Fuse were generating heat, which assisted in a more rapid melting of the Fuse's element,


[*] Circuit Breaker's contacts are welded closed, from continuous reclosing on a faulted circuit,


[*] Circuit Breaker is of the infamous "FPE Trip-Free", or "No-Blow Zinsco" designs,


[*] Motor Circuit is maybe not fed "Entirely" through the 20 Amp Breaker,


[*] Non-Selective coordination between the Feeder's OCPD and the Panelboard's OCPD.
</OL>

Sounds more likely that the Fuse was just a Fast Acting type.

At least the E base Fuse did not have a
"Capacity Extending Device"
or
"Trip Eliminator"
(AKA "Coin behind the Fuse")


Scott35