Double Neutral Panel

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codequestion

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I have from the transformer secondary conductors number and sized at 5-#2 AWG + 1-#6 AWG GND going to panel with double neutral. I looked at previous thread regarding this but still not sure where in NEC 2014 it says not to do this.
 
I would say the rule for minimum conductors size for parallel conductors.

JAP>
 
codequestion said:
I have from the transformer secondary conductors number and sized at 5-#2 AWG + 1-#6 AWG GND going to panel with double neutral. I looked at previous thread regarding this but still not sure where in NEC 2014 it says not to do this.
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200% neutral is pretty common. Nothing preventing you from doing it except the size as stated before is limited by 310.10.H
 
codequestion said:
I have from the transformer secondary conductors number and sized at 5-#2 AWG + 1-#6 AWG GND going to panel with double neutral. I looked at previous thread regarding this but still not sure where in NEC 2014 it says not to do this.
Click to expand...
What size transformer? Single phase or three? What is a double neutral? Two neutral bars?

Try again with explaining your installation. It sounds like you are paralleling 2 #2 for each phase of a single phase transformer with 1 #2 for the neutral. Plus the EG. Yes?

1/0 is the smallest conductor allowed to be paralleled.
 
codequestion said:
I have from the transformer secondary conductors number and sized at 5-#2 AWG + 1-#6 AWG GND going to panel with double neutral. I looked at previous thread regarding this but still not sure where in NEC 2014 it says not to do this.
Click to expand...

As mentioned the parallel #2's for the neutral is not code complaint. Also you should try to use the correct terminology to describe the "GND". It's not a "ground" it is the Supply Side Bonding Jumper (SSBJ).
 
Is this a technical installation like a server room or other electronics? Double neutrals are often specified (I always do) for harmonic current problems with large 120v electronic equipment loads.
 
Andy Delle said:
Is this a technical installation like a server room or other electronics? Double neutrals are often specified (I always do) for harmonic current problems with large 120v electronic equipment loads.
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Sorry guess should have added this. Its for huge government office with computers. I thought you can have one neutral to panel oversize but two going to same panelboard may present safety issue since if someone pulled one neutral and not the other when working on panel.

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codequestion said:
Sorry guess should have added this. Its for huge government office with computers. I thought you can have one neutral to panel oversize but two going to same panelboard may present safety issue since if someone pulled one neutral and not the other when working on panel.

Sent from my SM-G935U using Tapatalk
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Nobody is going to do that.

Parallel feeders are installed every day.

Although what you explained is paralleled with conductors that are too small to be allowed.

JAP>
 
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