2 pole 120v Breaker ?

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mjc

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Hi Guys , Need to throw this out there, never had to do this permanently and dont feel comfortable that its even gonna work. Here goes ....
Need to electronically meter a 20a, 2 pole circuit breaker to an electric heat load thru the use of CT's. The unit and display for the CT's will need 120volts. Is it NEC compliant to tap into this 20amp, 2 pole breaker that has a handle ty with #12 thhn to obtain 120volts ?

Thanks, Mike
(now that I think of it the 2 pole CB with a handle ty would still protect the thhn, it would be like having a multi-wire circuit [12-3] , and using a handle ty.) :eek:
 
Re: 2 pole 120v Breaker ?

Need to electronically meter a 20a, 2 pole circuit breaker to an electric heat load thru the use of CT's. The unit and display for the CT's will need 120volts. Is it NEC compliant to tap into this 20amp
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I have seen this done, if its code complaint I don't know but how else would you do it. The ones I have seen, if I recall right, just double lug the CT wires under the breaker lugs.
 
Re: 2 pole 120v Breaker ?

Poorly worded question.

My translation of the question: Can I run take two wires off of one pole of a 2 pole breaker and only one wire off of the other pole? this will give me one 240V circuit and one 120V protected by a single breaker?

My answer yes, if the breaker is rated to have two wires per terminal (like some SQD and C-H ones).
 
Re: 2 pole 120v Breaker ?

I don't think the question is about doubling the wires vs. using a pigtail.

It's about whether it's permissable to power a 120-v (line-to-neutral) and a 240-v (line-to-line) load from the same 2-pole breaker.

I say "yes", but with a caveat: the metering device may require fusing the power-supplying and the votage-sensing lead(s) below 20 amps.
 
Re: 2 pole 120v Breaker ?

It's not a problem:
econ_install.gif


"LOOK HERE"

For more info go "HERE"
 
Re: 2 pole 120v Breaker ?

Wayne is showing a page from the instructions for an E-mon watt-hour meter, which I've installed. Note the above-mentioned fuses on the voltage-sensing leads.

I just bought three in-line fuse-holders (I won't say where, but the initials are R. S. :cool: )and put 1-amp, 250-volt 3AG fuses in them.
 
Re: 2 pole 120v Breaker ?

Thanks Guys, this forem is the greatest.

Laryfine, your post on Jan. 20,06 @ 12:20am is right on and your second post at 10:17 was my thought also ' fuse holders w/ 3a glass fuses to protect equip, #12 thhn protected by the 20a breaker. My comfort zone has increased greatly knowing that the inspection should pass without a problem. :cool:

Mike -- Detrioit, MI
 
Re: 2 pole 120v Breaker ?

Opps! :eek: sorry Hurk, need to recognize you too!

Pictures are great I'm not using the Emon type of meter and CT, the unit is made by SQ.D but is very-very similar to the drawings you provided specially the power taps. Thanks again.

Mike - Det. MI
 
Re: 2 pole 120v Breaker ?

By Mike: Opps! sorry Hurk, need to recognize you too!
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Thats ok, I have used the E-Mon many times for remote and local power monitoring, They are nice little units that require very little to hook up, and with the split CT's they are a breeze to install. they can be fed from a separate two pole breaker as a multiwire circuit with neutral and be code compliant but if you cross which phase is connected with which CT it will not work. Also if you use a supply source that is different from the source supplying the load that the CT's are monitoring it won't work correctly.
 
Re: 2 pole 120v Breaker ?

I usually install larger meters, but I have never seen one that did not get its supply voltage from its monitoring voltage internal to the meter.

If this were a problem why could you not just pig tail a wire to one pole of the circuit being monitored.

The required fuses are usually internal to the meter or meter leads also. At least on the ones I have used. If not, an inline fuse would do just nicely.
 
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