Determine wiring configuration


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Old 08-23-03, 04:18 PM
rlowe
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Determine wiring configuration

Is there a way, possibly using a voltmeter, to determine which wire is HOT, which is NEUTRAL and which is GROUND?
 
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Old 08-23-03, 05:42 PM
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If the circuit is on, and working properly, the voltmeter will read 0V between neutral and ground, 120V between hot an neutral and 120V between hot and ground. If one of the three wires is green or bare, it is probably safe to assume that is ground.
This also assumes a standard lighting or recept. circuit, not a switch circuit.
 
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Old 08-23-03, 05:44 PM
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Generally, black is HOT, white is NEUTRAL, and green or bare is GROUND. If they are different colors, you can determine which is HOT, as it will be the one which shows voltage to both of the other two wires. Determining ground from neutral can be a bit trickier. Hopefully, the wires are the standard colors.
 
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Old 08-23-03, 06:11 PM
rlowe
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Thanks for the information. Unfortunately, all three wires were at some point spliced with white wires. I checked the voltage between the wires with the following results: Between wires 1 and 2 - 120V, between wires 1 and 3 - 60V and between wires 2 and 3 - 0V. I expected higher voltage between 1 and 3. Do these values show 1 as HOT, 2 as NEUTRAL and 3 as GROUND?
 
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Old 08-23-03, 06:58 PM
J
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Spend $15 on a "tick" tester. Your digital multimeter is being fooled by phantom voltage. 60 volts is a lie.

I would seriously consider having an electrician check out the electrical system, since your current wiring was obviously not done by somebody who cared about doing things right.
 
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Old 08-24-03, 06:52 AM
rlowe
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Thanks for the reply.... I traced the splice back and found it connected to BX cable with 2 cloth covered white and 1 black wire. Any way to determine how to connect new 14-2 Romex at this junction?
 
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Old 08-24-03, 08:00 AM
J
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Wire nuts in a junction box.
 
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Old 08-24-03, 09:40 AM
rlowe
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Yes, BUT back to my ORIGINAL question.... Which wires go together? Is it possible that the BX doesn't have a ground? This house is about 80 years old and some of the outlets are still only 2 pronged. If so, then maybe BLACK to BLACK. That leaves 2 WHITES from the BX. Which one should go to the ROMEX WHITE? I suspect wire - 2 - from my earlier post.
 
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Old 08-24-03, 05:53 PM
J
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If we're back to the original question, then I'm back to my original answer. Connect the black wire to whichever wire lights up the tick tester.
 
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Old 08-25-03, 03:43 PM
rlowe
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Your original answer didn't indicate any specific wire....but my last post asked specifically about the WHITE wire...
 
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Old 08-25-03, 05:26 PM
J
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Sorry. I know of no way to tell unless you can follow the wires back to where they come from, and unless when you follow them back you can identify an obvious grounding wire (i.e., it's bare or green or attached to a metal raceway).
 
 

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