Troubleshooting Heat Trace

[jmc24]

While troubleshooting a heat trace circuit, I checked continuity between the two conductors. There was continuity, but is this because of the semi conductor or is it likely that there is a short in the wiring? The circuit was not working, but the breaker did not trip as if there was a dead short in the circuit.

 

[ptonsparky]

While troubleshooting a heat trace circuit, I checked continuity between the two conductors. There was continuity, but is this because of the semi conductor or is it likely that there is a short in the wiring? The circuit was not working, but the breaker did not trip as if there was a dead short in the circuit.

Use an ohm meter, you need to know the resistance of the circuit. Continuity checks are just that, continuity.

Is there power applied to the cable?

 

[just the cowboy]

Check specs

Check specs

Heat trace has a ohms per foot rating I think. .And yes self limiting does use a semi conductor.

 

[jmc24]

Use an ohm meter, you need to know the resistance of the circuit. Continuity checks are just that, continuity.

Is there power applied to the cable?

No, there was no power applied to the cable. Both ends of the cable were unhooked and open, so my assumption was that there should be no continuity between the 2 conductors. Is that correct?

 

[just the cowboy]

No, there was no power applied to the cable. Both ends of the cable were unhooked and open, so my assumption was that there should be no continuity between the 2 conductors. Is that correct?

The heat trace cable is the load. Think of it as a bunch of small heater elements, one end connected to each conductor repeat many times.

 

[ActionDave]

No, there was no power applied to the cable. Both ends of the cable were unhooked and open, so my assumption was that there should be no continuity between the 2 conductors. Is that correct?

Incorrect. The heat tape is conductive throughout its entire length. The two conductors have to stay clear of each other or else you'll get a short circuit.

 

[Cow]

While troubleshooting a heat trace circuit, I checked continuity between the two conductors. There was continuity, but is this because of the semi conductor or is it likely that there is a short in the wiring? The circuit was not working, but the breaker did not trip as if there was a dead short in the circuit.

If it uses termination boxes at the end of the run, I would just put my meter on the terminals and very I had line voltage.

If it doesn't use termination boxes at the end, I would instead test power at the starter box and verify line voltage and then ohm the cable as Ptonsparky suggested.

 

[tom baker]

Heat cable has a negative temp coefficient, the colder the temp, the lower the resistance, hence more heat.
Check mfgs literature, get the ohms per foot/deg F