Using 3 wire for 2 wire application

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Old 11-07-19, 12:25 PM
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Using 3 wire for 2 wire application

OK. So I am planning on wiring up an outside shed and although it is a simple 2 way wire application, I just happen to have around 100 feet of outside 3 way wire. I want to use it since outside underground wire is not cheap.

I have two options, if I use the 3 way wire:

1) Simply leave the red wire unconnected. It would then get marette capped both inside the electrical panel and inside the first receptacle that it goes to in my shed.

2) Connect the red and black together in parallel, using a pigtail, capped with a marette, both in the electrical panel and the receptacle in the shed.

The benefit of #2 is to reduce the voltage drop across the 85 foot distance the electricity would travel. The wire is 12 awg and it is on a single pole 15 amp breaker. All the wiring in the shed is 14 awg wire. Just one low wattage light (60w) on the inside, a higher wattage light (300w) on the outside and one receptacle.

So which way would you guys go. I do worry about the guy who owns my property after me. I doubt either circuit would confuse you guys for too long but it probably would have confused me a little, if I came across it.
 
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Old 11-07-19, 01:11 PM
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Leave the red wire unconnected. Do not trim it in any way.

In the future it can become a second circuit sharing the (white) neutral.

Note: Upon entering the shed the cable must go first to a (15 amp) switch as a master switch. You can if you wish to install a 2 pole switch to control the red wire in the future.
 
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Old 11-07-19, 01:12 PM
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Option 1 is what you should do if you choose to use 3 conductor wire.
You shouldn't connect 2 wires together.
 
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Old 11-07-19, 08:18 PM
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The conductors are too small to parallel under the NEC.
 
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Old 11-08-19, 05:52 AM
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OK. Thanks for the suggestions. I'll just cap off the red wire and leave it unconnected.
 
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Old 11-08-19, 07:36 AM
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The conductors are too small to parallel under the NEC.
You can parallel small conductors, but there is no benefit as a single conductor is required to be sized to carry the entire load. So, really it would be redundant.

I agree with the others, keep it in there as a spare wire.
 
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