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Estwing magic
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Discussion Starter · #1 ·
Heat traced an above ground water supply pipe between two buildings but an alarm might be a good idea if the GFCI breaker trips. Any ideas? Audible would be okay but something that also sends a message to a smartphone would be perfect. Nice little upsell.
 

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i was going to suggest that but you beat me to it:laughing:
 

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Tool Fetish
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Critical heat trace shouldn't be on a gfci. It should not be plug-in style, it should be hard wired and be on a GFEP breaker, which trips at 30 ma, instead of 5 ma. If you are worried about alarming the installation, use the proper, quality material to start.
 

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Critical heat trace shouldn't be on a gfci. It should not be plug-in style, it should be hard wired and be on a GFEP breaker, which trips at 30 ma, instead of 5 ma. If you are worried about alarming the installation, use the proper, quality material to start.
I haven't been involved in a lot of heat trace but all of it has been as described above and power was supplied by a dedicated heat trace cabinet that was in turn tied to a PLC and god knows what else.
 

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Estwing magic
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Discussion Starter · #8 ·
Critical heat trace shouldn't be on a gfci. It should not be plug-in style, it should be hard wired and be on a GFEP breaker, which trips at 30 ma, instead of 5 ma. If you are worried about alarming the installation, use the proper, quality material to start.
So you're telling me 30mA protection doesn't trip?
 

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Cutler Hammer (and I'm sure others) make GFEP breakers with auxillary contacts wired into them..You could use that kind of a set-up and run whatever you like off the contacts..
 

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If you use a relay with the Gfi on the NC contacts the coil would have to remain energized right ? I don't know anything about heat trace (how long it stays on etc.) How long is that coil going to last ?
 

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If you use a relay with the Gfi on the NC contacts the coil would have to remain energized right ? I don't know anything about heat trace (how long it stays on etc.) How long is that coil going to last ?
Lots of heat trace, unless its MI or used for process temp control, stays on all the time. There are some heat trace controllers, relay panels, etc out there that cycle and monitor the heat trace based on pipe or ambient temps.
IMO, using a heat trace controller to turn off and on self regulating heat trace for pipe temps is a waste of money. It should be controlled by ambient temp and use the controller for your alarms..
 

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Estwing magic
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Discussion Starter · #15 ·
Cutler Hammer (and I'm sure others) make GFEP breakers with auxillary contacts wired into them..You could use that kind of a set-up and run whatever you like off the contacts..
It's a Homeline panel. Never thought much about 30mA equipment protection since it's a residential panel but they do make a 30mA breaker. Auxiliary contacts, I like that idea, might be tough with Homeline but it's worth checking out.
 

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We have hundreds of mechanical relays that are energized 24/7. Some are just the little ice cube relays and others are heavy duty control relays. They rarely ever burn out. Most of the burn out problems are caused by excessive cycling. That's where solid state relays come in. You can turn them on and off many times a second and they won't burn out. One thing to keep in mind with solid state relays is that when they burn up the fail in the on state which could be disastrous depending on the application.
 

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We have hundreds of mechanical relays that are energized 24/7. Some are just the little ice cube relays and others are heavy duty control relays. They rarely ever burn out. Most of the burn out problems are caused by excessive cycling. That's where solid state relays come in. You can turn them on and off many times a second and they won't burn out.
You work in a power generation plant ?
 

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Estwing magic
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Discussion Starter · #20 ·
Lots of heat trace, unless its MI or used for process temp control, stays on all the time. There are some heat trace controllers, relay panels, etc out there that cycle and monitor the heat trace based on pipe or ambient temps.
IMO, using a heat trace controller to turn off and on self regulating heat trace for pipe temps is a waste of money. It should be controlled by ambient temp and use the controller for your alarms..
I was told that at self reg should be controlled to shut off around 5 degrees C just to make sure it is completely shut off in warm weather. If it's cycling on and off just to maintain pipe temperature, that doesn't make much sense to me. I know that self reg does have inrush on startup. Repeating that inrush to maintain pipe temp probably isn't good.

For temp maintenance, probably MI or constant wattage cable is best.
 
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