220V two wires, why? 1

[2571]

Good afternoon,
I've encounter a situation that I need help understanding. We have two parking lot lights that share the same 220V source. When trouble shooting the reason for them not being on I had found there is only two wires. After asking a few other tradesmen why, there was no neutral I got the same responce "just because". If 120V circuit requires a neutral wire and 277V requires it, Why doesn't 208V or 220V? Is this normal or to code. What determines it the have a neutral or not?

Thank you in advance
2571

 

[Compositepro]

The first time I read the NEC I was very confused until I realized that there was a significan distinction between "the grounding conductor" (equipment to earth ground) and "the grounded conductor" (neutral).

 

[itsmoked]

Indeed! Very confusing until you get it clear in your head.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[itsmoked]

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[resqcapt19]

Electricity always follows the path of least resistance and can be unforgiving.

That is not the complete story...it also follows all other paths. It is these higher resistance paths that often ger us in trouble.
Don

 

[TheBlacksmith]

I was guilty of oversimplification, of course electricity follows multiple paths, it just that the human body has a low enough impedance to allow fatal levels of current flow if there is not a lower impedance path aka a properly conencted ground wire.

 

[Fieldbus]

I can't believe there are electricians out there who think that ground (that bit you stand on) is an effective conductor for the purposes of personal protection or that the neutral can be 'ditched' - I'd hate to wash my hands i his house just in case he'd wired up the tumble dryer.
Hasn't anyone heard of double insulated products? Perhaps they have never used portable hand held drills.
We (Europeans) always suspected that the US was the world's first equi-potential continental plane.

 

[jraef]

Fieldbus,
Most of this discussion was theoretical in nature. Of course we have "double insulated" appliances and equipment and our neutral conductors are insulated, that is what separates them from ground conductors. But at the utility transformer or at the sevice entrance (depending on local codes), there is a connection from the neutral conductor to ground reference. It is not legal to use ground as a conductor here, I'm sorry that you interpreted it that way and as far as itsmoked's comment about "ditching the neutral", one could only do that IF the light fixture was designed and listed to be used without a ground connection, essntially what you would refer to as "double insulated". The OP mentioned that the installation only had 2 wires, the electrician told him that this was all that was required. The electrician would have been the one to take responsibility at installation to ensure that the fixture was listed to be connected that way, so if he said that was all that was necessary, he was probably correct (assuming you trust electricians).

I hooked up my own tumble dryer and I bathed my infant children in the stainless steel sink. We are not electrical barbarians!.

JRaef.com
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