how to ID wire from junction or panel?

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Qwertyjjj

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I'm trying to identify some wires but the panel is labelled badly or not at all.
I've identified most of the circuits but I want to do some work on the baseboard heaters.
With the power off, is there a simple way to identify which wire leads to which heater by pulling it slightly? I have an electrical meter but the connections are not long enough to touch a wire at one end and the other...
 

LLigetfa

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I have used a tone generator that will trace the wires but without such a tool, you could use a simple clamp-on ammeter. Put a current load on the wire and test for the current.
 

DonL

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The best thing to do is kill the main and use a 2 piece, TRANS/REC Circuit tester that sends out and receives the signal.

Your heaters may be wired for 220V, so the double pole breakers may be the best to test first.


Good Luck.
 

DonL

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I have used a tone generator that will trace the wires but without such a tool, you could use a simple clamp-on ammeter. Put a current load on the wire and test for the current.

I doubled with you.

That will work also, but if it is broke, it may not be drawing Current.

A light-bulb makes a nice load.


Don't tell JWE on me.
 

Qwertyjjj

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There's nothing broken. I'm just trying to figure out where the wires go in the wall.
Also, it's a baseboard heater on 240vac so I can't plug in anything, ie no transmitter?
 

DonL

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There's nothing broken. I'm just trying to figure out where the wires go in the wall.
Also, it's a baseboard heater on 240vac so I can't plug in anything, ie no transmitter?


That is why you kill power to test it.

The wire has no clue what the voltage is.

You need a Pro, and/or PPE.
 

LLigetfa

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I have used an AM radio to "tone" out wires before. It will make a scratchy sound when you make/break the circuit.
 

Qwertyjjj

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That is why you kill power to test it.

The wire has no clue what the voltage is.

You need a Pro, and/or PPE.
Isn't a pro tester around $200+? ..or am I looking at the wrong things.
I was thinking of a more low cost way to do by pulling the wire and seeing which one moves near the panel.
 

DonL

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That may work, But staples may keep you from doing that.

Give it a try, Then double check with your volt meter.


Good Luck.
 

Jadnashua

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If you take the wires off of a circuit breaker, then twist or clip them together, when you go to the other end, look to see which one has the two power leads shorted together. That way, you can easily use your meter at one end.
 

DonL

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If you take the wires off of a circuit breaker, then twist or clip them together, when you go to the other end, look to see which one has the two power leads shorted together. That way, you can easily use your meter at one end.


Yep.

It is best to turn off the Main, If you work in the panel.

I have worked on hot panels, but the proper PPE should be used.

I like to respect electricity. It helps to know what you are working with.


Stabbing in the dark with a butter knife only works for Toasters.
 

Qwertyjjj

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The issue I have is that there is one 12/2 wire going from the panel to a junction box upstairs. In the junction box, parallel connections are made to 3 separate rooms but I cannot fully figure out which room is which as all the wire sheath is the same colour. I think the 3 wires go to the baseboards (1 in each room) but I am not absolutely sure.
 

LLigetfa

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If you cannot afford a meter, disconnect one wire and the heater it feeds will stop making heat. That then verifies that wire. Repeat for the second and infer the third.
 

DonL

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The issue I have is that there is one 12/2 wire going from the panel to a junction box upstairs. In the junction box, parallel connections are made to 3 separate rooms but I cannot fully figure out which room is which as all the wire sheath is the same colour. I think the 3 wires go to the baseboards (1 in each room) but I am not absolutely sure.

Is this correct "Bedroom 1: 24vac low voltage, 750W, thermostat is connected directly to a transformer on the baseboard." ?

Is there a relay in that box ?

Where is the 24Volts coming from / going to ?

The 24 Volts is for control, not the heating elements power.

If you turn off the breaker, That You think feeds that box, does anything else in the house stop working ?
 
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Qwertyjjj

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Is this correct "Bedroom 1: 24vac low voltage, 750W, thermostat is connected directly to a transformer on the baseboard." ?

Is there a relay in that box ?

Where is the 24Volts coming from / going to ?

The 24 Volts is for control, not the heating elements power.

If you turn off the breaker, That You think feeds that box, does anything else in the house stop working ?

I think it is a transformer+relay combined...it's a small box about 10cmx5cm housed inside the baseboard junction area.
The 24 volts goes directly to the low voltage thermostat but it's humming, which is also why I don;t want a transformer.
If I turn off the breaker, it turns off all 3 baseboards (plus the t-stats) but nothing else. It's on a 20A 2 pole at the panel. But I'm more concerned about which wire goes to which baseboard and whether they are daisy chained or if all the parallel connections are done in that junctionbox.
 

DonL

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I think it is a transformer+relay combined...it's a small box about 10cmx5cm housed inside the baseboard junction area.
The 24 volts goes directly to the low voltage thermostat but it's humming, which is also why I don;t want a transformer.
If I turn off the breaker, it turns off all 3 baseboards (plus the t-stats) but nothing else. It's on a 20A 2 pole at the panel. But I'm more concerned about which wire goes to which baseboard and whether they are daisy chained or if all the parallel connections are done in that junctionbox.


I don't think you can get around not using 24vac for the T-stat control for that unit.

At least not to meet code requirements. If you are self insured you can do as you please if you own the place.

Is the transformer humming or the T-stat ?
 

Qwertyjjj

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I don't think you can get around not using 24vac for the T-stat control for that unit.

At least not to meet code requirements. If you are self insured you can do as you please if you own the place.

Is the transformer humming or the T-stat ?
I'm replacing the baseboard for a new one as it's many years old. Why would I have to use 24vac? One of the 3 heaters already has a 240vac t-stat connected and that meets code doesn't it? :confused:
The transformer hums even when the t-stat is turned down to zero.
 

DonL

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I'm replacing the baseboard for a new one as it's many years old. Why would I have to use 24vac? One of the 3 heaters already has a 240vac t-stat connected and that meets code doesn't it? :confused:
The transformer hums even when the t-stat is turned down to zero.


It you replace it then the 240V stat will most likely be built into the unit, and designed to do that.

I thought you wanted to modify it. That is not allowed, and should not be done.
 
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LLigetfa

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A 24V T-stat only needs small gauge low voltage wire which is the reason for the relay. You cannot run 240V high current through the T-stat wire.
 

DonL

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A 24V T-stat only needs small gauge low voltage wire which is the reason for the relay. You cannot run 240V high current through the T-stat wire.


Not unless you like Toast a lot. lol


As for the transformer hum, You can remove the transformer and paint it with clear acrylic paint, then install it back before the paint dries. So the mount sticks, and don't vibrate. It will keep the lamination from making 60hz hum noise also.

Let it dry completely (overnight) before you restore power.


Good Luck on your project.
 
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