How to connect big wire to small terminal

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dahualin

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I have a rail yard project with several high mast lights 2000~3000ft away from lighting control panel. I am going to use 2 sets of #6 wire for voltage drop. The question is how can we connect #6 wires to 20amp circuit breaker. I don't think it works. Can we use smaller wire such as #10 to connect 2#6 wires with wire nuts inside LCP and connect to circuit breaker at the other end. Is it a code violation? Thanks.
 
dahualin said:
I have a rail yard project with several high mast lights 2000~3000ft away from lighting control panel. I am going to use 2 sets of #6 wire for voltage drop. The question is how can we connect #6 wires to 20amp circuit breaker. I don't think it works. Can we use smaller wire such as #10 to connect 2#6 wires with wire nuts inside LCP and connect to circuit breaker at the other end. Is it a code violation? Thanks.
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Is this "paralleling" in compliance with 310.4? :smile:
 
Very good catch. I will go only one set of 2#3,#3G wires for the high mast light. The question is still there. How can I connect the big wires to the small terminal of circuit breakers. Thanks.
 
dahualin said:
Very good catch. I will go only one set of 2#3,#3G wires for the high mast light. The question is still there. How can I connect the big wires to the small terminal of circuit breakers. Thanks.
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A short pigtail would seem to be in order.
 
You cant paralell conductors under 1/0, and you dont meet exceptions with your application, but the product you are looking for is called a pin connector. They crimp on the ends of the wire and reduce 1-2 AWG sizes for termiations. You can get them from burndy, ilsco, HMC.
 
a split bolt would look ugly, but be sure if you use a pin terminator that you have it on properly. They can be tricky and can introduce dielectric issues.

almost seems like a case for transforming.
 
another thought: 3000 feet of #2 has to be a ton of cash. would an engineered transformer estimate be out of the question?

engineers are cheap, ya know. :)
 
An Ilsco SPA2 butt splice has a range of #2 - #14 AWG. It is a set screw type in-line splice that is inexpensive and looks alot better that a split bolt connector.
 
dahualin said:
What can be used for the pigtail? A wirenut cannot used for #2 or #3 wires. Thanks.
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I have seen connectors used for this purpose. can't recall the brand name off the top of my head. might have been ilsco. they make a lot of odd but useful connectors.

You could also install a power distribution strip in the box for this purpose.
 
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large to small connections

large to small connections

I may be wrong but isn't large wire not supposed to be connected to small wire? sounds fishy to me?
 
Ok, ive been reading 310.4 Conductors in Parallel. Help my understand a little 'interpetation of code'.

It says no conductors smaller than 1/0 awg can be in parrallel, However when one run basic circuits for lets say receptacles and you have a j box up on the ceiling and you parrallel the circuits to the other receptacles so that the if one goes out the others still work, Help me out here in reconciling code. why is it you can parrallel these circuits, but this article says not to. not to mention the neutral is NOT to be dependent on the recetacles so the continuity continues.
 
brother said:
Ok, ive been reading 310.4 Conductors in Parallel. Help my understand a little 'interpetation of code'.

It says no conductors smaller than 1/0 awg can be in parrallel, However when one run basic circuits for lets say receptacles and you have a j box up on the ceiling and you parrallel the circuits to the other receptacles so that the if one goes out the others still work, Help me out here in reconciling code. why is it you can parrallel these circuits, but this article says not to. not to mention the neutral is NOT to be dependent on the recetacles so the continuity continues.
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You're confusing the term parallel conductors. In this case it would be two conductors connected at each end to effectively form one conductor. Not the same as a parallel circuit.
 
dahualin said:
I have a rail yard project with several high mast lights 2000~3000ft away from lighting control panel. I am going to use 2 sets of #6 wire for voltage drop. The question is how can we connect #6 wires to 20amp circuit breaker. I don't think it works. Can we use smaller wire such as #10 to connect 2#6 wires with wire nuts inside LCP and connect to circuit breaker at the other end. Is it a code violation? Thanks.
Click to expand...
Couple of questions here... What kind of load will each of the high mast lights have??? What voltage? What is the distance from the panel to the lights on top of the high masts? Could each high mast have it's own circuit?
 
hulk said:
I may be wrong but isn't large wire not supposed to be connected to small wire? sounds fishy to me?
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there is no such rule. as long as the smaller wire is protected by the BC OCPD, it is quite acceptable.
 
captaincrab55 said:
Couple of questions here... What kind of load will each of the high mast lights have??? What voltage? What is the distance from the panel to the lights on top of the high masts? Could each high mast have it's own circuit?
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We have 8 high masts at rail platform area. Each high mast is 8400VA 480V single phase with one circuit. The longest distance from high mast to LCP is 3000ft.
 
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