Portable GFI for space heater

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lpranger467

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My spaceheater keeps blowing the fuse in my unit when on high (1500w). A friend suggested drilling a hole ro run an extension cord directly to hook up box at RV park, I want to make sure my family has some sort of protection though and wonder if a GFI extension cord at the plug would do the trick
 

Lou Schneider

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Any park built or rewired in the last 25 or so years already has GFCI on their 15/20 amp pedestal outlets because they're assuming they'll be used outdoors where someone is actively grounded. GFCI only protects against voltage leaking to ground. That's much less likely in the insulated interior of an RV.
 
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lpranger467

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Any park built or rewired in the last 25 or so years already has GFCI on their 15/20 amp pedestal outlets because they're assuming they'll be used outdoors where someone is actively grounded. GFCI only protects against voltage leaking to ground. That's much less likely in the insulated interior of an RV.
Thanks, would it provide extra protection from the heater overheating though ? I will need to leave heaters on when I'm at work and my pets are left alonre. I just want some extra protection so the trailers fuse wont blow and leave them without a space heater
 

Lou Schneider

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Nope, GFCI only protects against current leakage to ground, possibly by shocking someone who's grounded. Not likely in an insulated RV.
 

Rob&Deryl

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Your heater draws too much for your circuit. Running an extension cord to the pedestal May work if
1) the pedestal has a 20a circuit and
2) the cord is rated for the load & distance

I would not use a cord lighter than #12
Better would be slightly lower power heater.
 

John From Detroit

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As Lou said any park built in the last several years the 20 amp is GFCI
You can also get GFCI cords
or you can make your own GFCI cord (12 ga cord I'd go with a 20 amp plug but you might need a 15 (More on that in a bit) and a 20 amp GFCI outlet with box and cable clamp and cover (standard surface mount outlet box)

In fact I have one.


I f you have slideouts you might be able to snake the cord out at the end of one via the seals without drilling.

Now 15/20 amp plugs (Make sure you get a 120 volt 20 amp)

15 Amp look like this | |
20 amp look like this | -- or -- |
I left off the safety ground pin in the ascii drawing because 1: I don't know how to put it in but the difference between 120 and 240 volt plugs is WHICH of the two blades is turned 90 degrees

Why use a 20 amp plug for a 12.5 amp load... (I believe in overkill when it comes to this kind of thing)

Talkes longer to burn up of course.
 

lpranger467

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Your heater draws too much for your circuit. Running an extension cord to the pedestal May work if
1) the pedestal has a 20a circuit and
2) the cord is rated for the load & distance

I would not use a cord lighter than #12
Better would be slightly lower power heater.
I know its a 20amp coming from the supply so I was hoping by going direct to the source and not through the trailers plugs that I would be less likely to throw a circuit.
 

lpranger467

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As Lou said any park built in the last several years the 20 amp is GFCI
You can also get GFCI cords
or you can make your own GFCI cord (12 ga cord I'd go with a 20 amp plug but you might need a 15 (More on that in a bit) and a 20 amp GFCI outlet with box and cable clamp and cover (standard surface mount outlet box)

In fact I have one.


I f you have slideouts you might be able to snake the cord out at the end of one via the seals without drilling.

Now 15/20 amp plugs (Make sure you get a 120 volt 20 amp)

15 Amp look like this | |
20 amp look like this | -- or -- |
I left off the safety ground pin in the ascii drawing because 1: I don't know how to put it in but the difference between 120 and 240 volt plugs is WHICH of the two blades is turned 90 degrees

Why use a 20 amp plug for a 12.5 amp load... (I believe in overkill when it comes to this kind of thing)

Talkes longer to burn up of course.
Thanks very much
 

Ex-Calif

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I posted in your other thread.

 

NY_Dutch

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Just to be clear, a GFCI outlet or breaker does not need or use a ground. It works by sensing a tiny imbalance in the current flow in the hot and neutral legs. The ground connection on a GFCI outlet is only there as a pass through for the safety ground. GFCI breakers have no ground connection at all.
 
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lpranger467

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Just to be clear, a GFCI outlet or breaker does not need or use a ground. It works by sensing a tiny imbalance in the current flow in the hot and neutral legs. The ground connection on a GFCI outlet is only there as a pass through for the safety ground. GFCI breakers have no ground connection at all.
I may be doing a belt and suspenders approach then, I worried that by using an extension cord for my space heater would be bypassing the safety aspect (for overheating) that the trailers fuse system provided. My wife and pets will be in the trailer while I'm at work so I didnt mind spending the extra money, may have not been needed though I guess
 

Rene T

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Have you tried plugging it in another outlet/circuit? It may be that something else drawing a lot of power on the same circuit and that’s what causing the breaker to trip. Find another outlet on a different circuit.
 

NY_Dutch

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I may be doing a belt and suspenders approach then, I worried that by using an extension cord for my space heater would be bypassing the safety aspect (for overheating) that the trailers fuse system provided. My wife and pets will be in the trailer while I'm at work so I didnt mind spending the extra money, may have not been needed though I guess
The park stanchion typically has a 15 or 20 amp breaker for the GFCI utility outlet. Between the breaker and the GFCI, you're as well protected as you would be plugging the heater into an outlet at home. Just make sure the extension cord is heavy enough for the heater load. 12 gauge wire would be the usual recommendation unless the extension cord is extremely long.
 

lpranger467

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Have you tried plugging it in another outlet/circuit? It may be that something else drawing a lot of power on the same circuit and that’s what causing the breaker to trip. Find another outlet on a different circuit.
There were some light on that circuit but I didnt figure that would draw much
 

Rene T

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There were some light on that circuit but I didnt figure that would draw much
Your lights are typically 12 volt DC. All the outlets will be 110 volt AC. Your CONverter could be tied into that circuit because it’s trying to charge your battery and also supple power for those lights.
When you trip the breaker from the heater, go around and see if anything else is off.
 

CharlesinGA

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As Lou said any park built in the last several years the 20 amp is GFCI
You can also get GFCI cords
or you can make your own GFCI cord (12 ga cord I'd go with a 20 amp plug but you might need a 15 (More on that in a bit) and a 20 amp GFCI outlet with box and cable clamp and cover (standard surface mount outlet box)

In fact I have one.


I f you have slideouts you might be able to snake the cord out at the end of one via the seals without drilling.

Now 15/20 amp plugs (Make sure you get a 120 volt 20 amp)

15 Amp look like this | |
20 amp look like this | -- or -- |
I left off the safety ground pin in the ascii drawing because 1: I don't know how to put it in but the difference between 120 and 240 volt plugs is WHICH of the two blades is turned 90 degrees

Why use a 20 amp plug for a 12.5 amp load... (I believe in overkill when it comes to this kind of thing)

Talkes longer to burn up of course.
If the OP were to buy a real 20 amp plug for the end of the extension cord, they would likely find that they could not use it. You don't often stumble into 20 amp receptacles. Fact is, there is the same amount of metal in the blades of a 15 amp as there is a 20 amp plug. Of course, by code, you have to attach a 20 amp plug to a 12 gauge cord. The OP does not even need a 12 gauge cord. A 14 gauge cord will work just fine for a 1500 watt heater, provided the run is reasonably short, certainly less than 50 ft.

As far as receptacles go, on quality ones, such as commercial or industrial grade, the difference between a 15 amp and a 20 amp is.......... the plastic face. If you peer down into the neutral slot of a 15 amp receptacle (again, I emphasize, a quality receptacle) you will see the same innards, including the horizontal contacts, used in a 20 amp version, just that they are blocked off by the face.

If the OP needs a GFCI (and they should not, as the park pedestal will have to have a GFCI for both code compliance and liability reasons, either a GFCI receptacle or a GFCI circuit breaker) then there are a number of separate GFCI units on the market. I have one of these and it seems to be a good one. It tests ok when I use a GFCI tester on it and I have run a 120v air compressor drawing 17 amps thru it for a couple or three hours on occasion blowing water out of a 1500 gallon well tank.

Husky Wall Adapter GFCI

husky-gfci-plugs-04-00106-64_145.jpg


Charles
 

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lpranger467

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Thanks for both recent replies, when the fuse blew I know it took a lot of the lights with it. The one addition possibly to that circuit could have been the fridge, I didnt think to check it at the time (it was cold and I wanted to just get the heater going again) but I will check to see if the fridge was running on that same circuit.
 

Rene T

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Thanks for both recent replies, when the fuse blew I know it took a lot of the lights with it. The one addition possibly to that circuit could have been the fridge, I didnt think to check it at the time (it was cold and I wanted to just get the heater going again) but I will check to see if the fridge was running on that same circuit.
Your lights should have stayed on powered by your battery. Now if you don’t have a battery or yours is dead, the lights may have only been powered by the CONverter. And if the converter was on the same circuit that will explain why the lights went out.
The next time this happens and while the lights are out, go around looking for a wall receptacle which still has power. Plug the heater into that outlet.
 

lpranger467

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Traverse City
Your lights should have stayed on powered by your battery. Now if you don’t have a battery or yours is dead, the lights may have only been powered by the CONverter. And if the converter was on the same circuit that will explain why the lights went out.
The next time this happens and while the lights are out, go around looking for a wall receptacle which still has power. Plug the heater into that outlet.
Thanks Rene, I will be back to the trailer in 5 days, I'm going to see if the fridge was on the same circuit as well. I appreciate you taking the time to help me, we have camped for years but never had to use a camper in the winter (when its 17 degree out), there is certainly a learning curve.
 

Lou Schneider

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Is your refrigerator a gas-electric RV fridge? If so, it works by boiling a water and ammonia mixture and you may have to add some supplemental heat to the rear of the enclosure to keep it working when it gets that cold. It also draws about 300-500 watts in electric mode which can be an additional load (2.5-5 amps) on your electric supply.
 
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