Electrical help pls, what amperage is this breaker

Unsure of how breakers are notated for 240 V, this is on my water heater circuit, see position 13-15. This is a double/ganged breaker, I think this is 40A total for the 240V, and not 80 total, right? 40A on each 120, so 40 total on the 240? thanks.

 

40

 

2 pole 40amp

 

40 amp at 240 volts,
2X 40 amp at 120 volts

 

That's why they put"40" on the breaker. Jack.

 

He was probably hoping for a 9mm or .45 breaker instead of a fo-tay.

 

They really don't want consumers doing math

 

No one likes 40 here....even in electrical service boxes.

 

which one?, the one that says 40 or the one that says 30? or the one that says 60?

i'm sorry, i can't help it sometimes...

 

I was ready, too, but he had this in there:

 

in a 120 v system, there is a hot lead, and a return lead. In the USA the hot lead is colored black, and the return lead is white. If the white lead gets cut, and touches earth ground somewhere....nothing happens as the return lead is also at 0 volts (approximately). So in a 120V system, you only need to fuse the hot lead.

But in a 240 V system, it is really comprised of TWO 120V circuits. I guess you can think of one as being Positive polarity, and the other negative polarity. If EITHER of these two hot leads is cut and touches earth ground, there will be a short circuit and a big arc of current forms. You do not know ahead of time if the positive lead, or the negative lead will be the one short circuiting, so you have to put a circuit breaker on BOTH hot leads. If Either of them shorts out, you want to turn off the other one, even if it is not short circuited, for safety reasons, so the two circuit breakers are ganged together with a physical bar.

Normally current flows out of the positive lead circuit breaker, to the load, then back to the negative lead circuit breaker, completing the circuit loop. NO current should flow in the neutral wire at all. So even though there are two 40 amp circuit breakers, the actual current in the loop is only 40 amps. The same 40 amps flows thru each breaker.

 

Looks like you got your answer. To simplify———
A 240v 40a breaker is 40a total. Not 80.

 

Wanna really blow his mind...

 

I wired this once. The hard part was getting the Holy Water to remain Holy.

 

"We really try and discourage people from arithmetic".

-- Marsha​

 

you ONLY use one of those if you need to reverse the polarity of the neutron flow

 

How to wire water heater thermostats

 

Test it with a wet finger. I'll have to check the book on those positions...never got that far!

 

Hahahaha!!!!!

 

Yep... where 120+120=208.

 

And 120+120+120 = 208 as well.

 

The flux converter needs to be in temporal phase

 

All the current is lagging by 90 degrees.

 

If it runs backwards change any two wires. (3phase, that is) Jack.

 

Yep 120 degree phase diff says Nikola Tesla

 

I always change the outer two to reverse direction

 

I would have put my money on the ee, or the warm front.

 

Good chance it is 40.