# Neutral Wire

Discussion in 'General Electronics Chat' started by electronewb, Nov 5, 2012.

1. ### electronewb Thread Starter Member

Apr 24, 2012
260
3
it's been covered he a few times but I just read a few article on the subject of neutral wire in an electric system. Let me know if I got it right

240V from the pole transformer
splits in 2 feeds 120VAC on one leg and 120VAC on the other leg
center tap of the transformer carries the neutral that goes to the ground carrying no voltage?

2. ### crutschow Expert

Mar 14, 2008
12,558
3,078
True. The 240V winding on the mains transformer has a center-tap which is connected to earth ground and thus is called the neutral since it normally has no significant voltage as measured to ground (but it does carry current). The voltage across the two hot leads is 240V and the voltage from each hot lead to neutral is 120V.

3. ### wmodavis Well-Known Member

Oct 23, 2010
737
149
Note the way crutschow worded it - " it normally has no significant voltage as measured to ground"

With respect to either 240 V legs it does carry 120V.

4. ### crutschow Expert

Mar 14, 2008
12,558
3,078
Define "carry".

The normal voltage of the neutral to ground is near zero, generated only by any current through the neutral wire times the wire resistance.

The voltage from either hot wire to the neutral is 120V but I wouldn't say the neutral "carries" 120V. That's confusing to me.

Sparky49 likes this.
5. ### Sparky49 Active Member

Jul 16, 2011
834
417
Yeah, remember voltage is potential difference.

The difference in potential between two points. I think you mean to agree with crutschow, the neutral can 'carry' current.

6. ### electronewb Thread Starter Member

Apr 24, 2012
260
3
So is the neutral the ground for the transformer? Since neutral and ground eventually get tie together in the breaker box.

7. ### MrChips Moderator

Oct 2, 2009
12,242
3,283
It is not a good idea to think that NEUTRAL is the GROUND for the transformer.

NEUTRAL is the RETURN path for the transformer. Current flows through the NEUTRAL.

No current should flow through the GROUND.

8. ### electronewb Thread Starter Member

Apr 24, 2012
260
3
But eventually ground and neutral get tie together

http://www.brightok.net/~rlindho/house/wiring/electwiring.html

Below the breaker box picture

The white wire is connected to the common neutral bus. But for this circuit we have a copper ground wire that is connected to the common neutral bus and to the ground bus leading out to a ground rod