#4thhn on a 20 amp breaker

[Sekrubas73]

I am running #4 thhn for site lighting. It is a 20 amp circuit but because of voltage drop was upsized to #4 required by the electrical engineer who drew up the plans. My question is how do you terminate these conductors on a 20 amp breaker as well as on the contactor that is controlling it? I believe these two devices are only good for #10.

 

[roger]

You could use a pin type terminal crimped to the #4 but, I would just splice a piece of #10 on to the #4 in the panel and contactor.

Roger

 

[Mulrooney]

You could bring your #4's into a can next to the contactor and splice them to 10's, then run 10's between contactor and breaker. This few feet won't effect voltage drop.

 

[Mulrooney]

could also increase the size of your contactor and breaker

 

[roger]

You could bring your #4's into a can next to the contactor and splice them to 10's, then run 10's between contactor and breaker.

He could, but unless these splices filled any cross sectional area of the enclosure to 75% it wouldn't be neccessary, the splices could be in the contactor.

Roger

 

[Jim W in Tampa]

I would just splice in the panel. Only remote issue is what the specs called for. As to legal by nec yes. Your voltage drop as been said will not be issue over the last few feet.

 

[Dennis Alwon]

Did you upsize your egc to #4. art. 250.122(B)?

 

[nhfire77]

Did you upsize your egc to #4. art. 250.122(B)?

I'm telling Charlie you said that

 

[Dennis Alwon]

I'm telling Charlie you said that

Oh no the not the mod squad. :grin:

 

[petersonra]

You could use a pin type terminal crimped to the #4 but, I would just splice a piece of #10 on to the #4 in the panel and contactor.

Roger

I vote for the splice as well. Although a couple of small DIN rail mounted terminals might be neater looking if there is room for them.

 

[charlie b]

I'm telling Charlie you said that

I never said you shouldn't. I said you shouldn't have to. But you do have to, for at least the next code cycle.

 

[jetlag]

Take out your dikes and on the back side of the #4 take out just enough strands to go in the breaker, will be no voltage drop and you wont have to get in a conversation with any one about the splices. Also look at breakers some brands have more room for larger conductor , Get the 20 amp with most room and box to match.

 

[petersonra]

Take out your dikes and on the back side of the #4 take out just enough strands to go in the breaker, will be no voltage drop and you wont have to get in a conversation with any one about the splices. Also look at breakers some brands have more room for larger conductor , Get the 20 amp with most room and box to match.

I am trying to think what rule you would be breaking if you did this. It can't be this simple.

 

[iwire]

I am trying to think what rule you would be breaking if you did this. It can't be this simple.

The listing of the breaker.

 

[jetlag]

I am trying to think what rule you would be breaking if you did this. It can't be this simple.

Well you could go to the trouble to figure the circular mills of the the strands left on and prove they add up to #12 or more. I would much rather have that then see a #10 wire nutted to a #4 at every terminal . You must have one heck of a run to require that size wire. I would run the 4 from a 60 a 220 breaker to a sub panel and feed the #12's off that.

 

[iwire]

Well you could go to the trouble to figure the circular mills of the the strands left on and prove they add up to #12 or more.

No you can not add them up and prove that it is anything.

A breaker rated for wire sizes 6 to 14 cannot have a conductor labeled 4 AWG connected to it without an NEC violation.

I would much rather have that then see a #10 wire nutted to a #4 at every terminal .

Why in the world would you prefer a hack move over a professional splice?

You must have one heck of a run to require that size wire. I would run the 4 from a 60 a 220 breaker to a sub panel and feed the #12's off that.

We often use 4 or larger for site lighting circuits.

 

[jetlag]

No you can not add them up and prove that it is anything.

A breaker rated for wire sizes 6 to 14 cannot have a conductor labeled 4 AWG connected to it without an NEC violation.





Why in the world would you prefer a hack move over a professional splice?




We often use 4 or larger for site lighting circuits.

I use #4 for that also but its more than a 20a breaker , cant put to many lights on that. I would still snip the wire if not getting inspected , only take a strand or 2 to get to #6 . But I belive the purpose of the wire rating on the breaker is to let you know that is the only wire sizes that fit the breaker lug but they are not trying to establish a code on the wire size. Would you really worry about 20 amp going thru a #4 with couple of strands gone ? How often does a strand or two get pushed back on a wire nut and not be connected when all the strands are needed to comply.

 

[Cow]

Haircutting is lazy, making excuses to try and persuade everyone on here that's it's not laziness, is just silly.

A J-box beside the panel with distribution blocks would probably be my preferred method.

 

[roger]

a 20a breaker , cant put to many lights on that.

At 277 or 480 volts a good number can be served.

Roger

 

[jetlag]

At 277 or 480 volts a good number can be served.

Roger

Thats true , last one I was called to work on had a 60a , 240 volt breaker and # 4 conductors running underground out in the parking lot to a stadium light in the center. When I opened the access panel all the # 10 conductors running to 4 other lights were all spliced into the #4. One of the lights had shorted out and melted the insulation to that light before the breaker tripped . I set a 100a main lug outside panel at the base of the center pole and put the lights on 20 a breakers . I then pulled in new #10 to the bad light and installed a new fixture. Thats why I hesitate to splice the #10 to #4 on at least the far end of line . Some jack leg slap in a bigger breaker. Thats same reason I dislike tap conductors , just because they set a limit on the length doesnt keep them from melting