Breaker replacement

[xformer]

A customer has a concern about an old 60A 2 pole humming push-o-matic

breaker feeding a water heater. Upon closing, the breaker hums. Is this a

safety concern or fire hazard? Should the breaker be replaced? Or, is he worried

about nothing?

 

[augie47]

humming is not necessarily a problem....
what size wire and what size (watts) heater.. 60 amp is UNUSUAL for a residential water heater.

 

[LarryFine]

X, try measuring from line to load (panel bus to load conductor) across each pole of the breaker while under load. This voltage is called 'fall of potential' and will disclose undue voltage drop.

 

[xformer]

Thanks Augie, Thanks Larry

 

[480sparky]

......... 60 amp is UNUSUAL for a residential water heater.

I'll bet a nickel that the circuit also supplies the dryer, range or air conditioner condenser.

 

[Volta]

I'll bet a nickel that the circuit also supplies the dryer, range or air conditioner condenser.

As in a split-bus OCP device?

 

[augie47]

I'll bet a nickel that the circuit also supplies the dryer, range or air conditioner condenser.

I'd have to bet with you.

 

[xformer]

As in a split-bus OCP device?

Split buss??

 

[augie47]

Some older panels had a break in the panel buss and one of the "main" breakers would actually feed a set of branch breakers in the same panel.
On these, often you would have 3 or 4 dp breakers to range, heat, etc and then 1 or 2 dp breakers which fed the one below them.
It was a means to limit your mains to no more than 6 and still have 1 panel.
As I reall, it was a common push-matic panel.

 

[480sparky]

As in a split-bus OCP device?

No... one breaker serves two loads.

 

[Jraef]

Just had a flashback of Frank Zappa's "Dinah-Moe Humm"...

If it were anything other than Pushmatic, I wouldn't be concerned about the hum. But because of the nature of how a Pushmatic hold the circuit closed, that bothers me a lot. the Line-Load voltage test should be a good guide as to integrity though.

 

[brian john]

Humming can also mean the CB is in the long time trip range and be close to tripping or a variety of other issues, for the cost of the CB I would replace it.

There are lots of resellers with this product.

http://www.aplussupply.com/break/push/push.htm