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#### hotblueelectric

· Rolling Thunder
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Ok let me see if I have this right. I'm running (2) 120 volt circuits 375 feet for two gate openers that use 12 amps starting and 8.5 amps running. I will be installing (2) # 4's on 20 amp circuit breakers, and (1) #10 neutral and one #10 ground. All in pvc. This should keep my voltage drop to 2%. Do these calculations look correct. Any comments are appreciated.

#### FrunkSlammer

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7,205 Posts
What is the load current? Oh never mind, you said it. Let me check my code book and see what I get.

Rough calculation I get you could use something closer to a #6-#8. I'd have to get a pencil and paper to do a solid calc.

#### RFguy

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403 Posts
Why a reduced neutral when running 2 x 120 volt circuits? I know a reduced neutral is normal when there are mixed 240 volt and 120 volt loads, but should you do it when you are only running 120 volt circuits?

#### someonespecial

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Why a reduced neutral when running 2 x 120 volt circuits? I know a reduced neutral is normal when there are mixed 240 volt and 120 volt loads, but should you do it when you are only running 120 volt circuits?
Because they will likely be fed from different poles and reduce the current on the neutral.

#### RandyM

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282 Posts
What if only 1 is running? It will need a full size neutral. You could put a SQ D AC disconnect at the first one and swap out the dummy CB for 2 QO120 CB's.

#### FrunkSlammer

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I would run a full size neutral, but I would probably run #8 instead of #4 and put it on a 15A breaker anyway… not that that makes any difference.

#### macmikeman

· Senile Member
I make all the electrons line up for their Flu shots
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Ok let me see if I have this right. I'm running (2) 120 volt circuits 375 feet for two gate openers that use 12 amps starting and 8.5 amps running. I will be installing (2) # 4's on 20 amp circuit breakers, and (1) #10 neutral and one #10 ground. All in pvc. This should keep my voltage drop to 2%. Do these calculations look correct. Any comments are appreciated.

Do what calculations look correct? You posted your results only , not your calcs. Show us how you arrived at those sizes and then we approve or not. I have apps on my computer that do all the work, but those are not my calculations.

#### 99cents

· Moderator
Estwing magic
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Ok let me see if I have this right. I'm running (2) 120 volt circuits 375 feet for two gate openers that use 12 amps starting and 8.5 amps running. I will be installing (2) # 4's on 20 amp circuit breakers, and (1) #10 neutral and one #10 ground. All in pvc. This should keep my voltage drop to 2%. Do these calculations look correct. Any comments are appreciated.
The calculation is probably okay but is there any reason you need 2% VD?

#### hotblueelectric

· Rolling Thunder
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84 Posts
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Ok I will figure at 3% VD. 120volts, copper, 1 phase, 375 feet, and use the running amps for each at 8.5 amps. I come up with #6 for each hot, a #6 for neutral and #6 for ECG.

Using #6
2x12.9x375x8.5 = 822375/26240 = 3.13 VD

#### 99cents

· Moderator
Estwing magic
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Ok I will figure at 3% VD. 120volts, copper, 1 phase, 375 feet, and use the running amps for each at 8.5 amps. I come up with #6 for each hot, a #6 for neutral and #6 for ECG.

Using #6
2x12.9x375x8.5 = 822375/26240 = 3.13 VD
I would aim for 4 to 5% VD and go with Frunk's suggestion.

#### MDShunk

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20,945 Posts
What's the voltage at the supply end, and what's the dataplate voltage tolerances on the opener? Might not even need to care about voltage drop.

#### MTW

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Ok let me see if I have this right. I'm running (2) 120 volt circuits 375 feet for two gate openers that use 12 amps starting and 8.5 amps running. I will be installing (2) # 4's on 20 amp circuit breakers, and (1) #10 neutral and one #10 ground. All in pvc. This should keep my voltage drop to 2%. Do these calculations look correct. Any comments are appreciated.
Your EGC needs to be full sized as well.

#### Bkessler

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5,678 Posts
375' isn't that far. #10s on a 15 amp breaker seems reasonable.

#### FrunkSlammer

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Yeah #10 would get you somewhere around a 3% VD.

If I was worried about it, I'd just go #8 so long as it's coming out of the customers pocket and not mine.