Community Forums

miniceptor86 · 03-20-2017, 02:08 PM

Look at the extension cord or its package it should have the wire gauge, American Wire Guage " AWG " on the cord and the package. To run your heater you should have 12 Guage wire in my opinion as this is what the national electric code specifies for 20 amp household wiring. 12 guage extension cords are not an every day, easily found item and the cost might make you blink. Most likely not what you bought at wal mart, or most hardware stores. You are trying to pull to much current (amps) through wire and connectors that aren't able to handle the amperage.The circuit breaker in the garage are to protect the wiring from the breaker box to the outlet. The outlet has a specific configuration to match cords of proper wire guage. You have spliced in via the adapters wire not rated to handle 30 amps.

The 30 amp breaker will not trip until somewhere near thirty amps is flowing. Once in the camper the breakers are protecting the wiring in the camper from the breaker to the outlet. The breakers there are not tripping because the heaters are on separate circuits and breakers and they are not drawing enough current in the individual camper circuits to trip the breaker. The total amperage of the heaters is however combined in your extension cord which I'm guessing is most likely 16 guage wire. I'm not familiar with what 16 guage is rated for but 14 is rated for 15 amps which as said before is close to what one heater is drawing. (Wire guage is rather counter intuitive, the larger the number the smaller the wire).

To make your heaters work safely you'll need to get an 30 amp RV extension cord. These have the connectors and insulation to provide safe current flow for a maximum of two heaters.

dmurdock · 03-20-2017, 02:40 PM

Quote:

Originally Posted by Skrewball

My main cords going out are 30s and I have that adapter than converts to 15 but my roomate plugged that conversion into a 30a wall socket in the house. Should I move it to a 20a?

Basically the weakest link in your entire chain (cords/plugs/breakers/etc...) is the limit. The plug in your house is a 15 or 20 amp plug (I think they are 15) on a 30 amp breaker..the breaker can handle 30 amps but remember it's feeding 4 or 5 plugs in the house. If you look at the end of your extension cord in the pic it says "15A" so that's 15 amps at 120 volts = 1800 watts..and that 1800 is in ideal situation. If you are going to be using a plug in the house 15A should be your limit. watts = volts x amps so you can look at the items in your RV and figure out what you want to run at once. The suggestion for a "kill a watt" is a great idea because once you plug the RV in there are probably some items you aren't aware of using some energy and the kill a watt will enable you to calculate what you have left. One space heater with nothing else running will be pushing it right up to the limit.

Isaac-1 · 03-20-2017, 04:19 PM

If you have a 30 amp breaker in the house feeding a 120VAC 15 amp or 20 amp outlet (or chain of outlets) this is an electrical code violation and could potentially start a fire. Depending on how old the house is, you may have multiple 120VAC 15 or 20 amp outlets connected to a 20 amp breaker, although more common is to have them connected to a 15 amp breaker. Both 120VAC 15 and 20 amp outlets have the same overall plug size, 120VAC 15 amp outlets are the size that almost all small appliances use from can openers to refrigerators and have the common 2 (II) blade connectors, sometimes with a 3rd round ground wire. The relatively rare 120VAC 20 amp cord has a T blade layout which may be found on more commercial equipment (most people own nothing with this style cord) although 120VAC 20 amp outlets will accept either 15 or 20 amp cords.

triplewide · 03-21-2017, 03:56 AM

Quote:

Originally Posted by Isaac-1

If you have a 30 amp breaker in the house feeding a 120VAC 15 amp or 20 amp outlet (or chain of outlets) this is an electrical code violation and could potentially start a fire. Depending on how old the house is, you may have multiple 120VAC 15 or 20 amp outlets connected to a 20 amp breaker, although more common is to have them connected to a 15 amp breaker. Both 120VAC 15 and 20 amp outlets have the same overall plug size, 120VAC 15 amp outlets are the size that almost all small appliances use from can openers to refrigerators and have the common 2 (II) blade connectors, sometimes with a 3rd round ground wire. The relatively rare 120VAC 20 amp cord has a T blade layout which may be found on more commercial equipment (most people own nothing with this style cord) although 120VAC 20 amp outlets will accept either 15 or 20 amp cords.

X2

You have a 30 amp breaker in the house/garage feeding a 30 amp demand RV. The space heaters are probably maxing out the RV demand. In between the the house/garage 30 amp breaker/fuse and the RV you have inadequate sized 15 amp wiring. This setup is a fire waiting to happen. Not only in the cords and the RV but the house wiring feeding the outlet you are plugged into. The melted cords are trying to tell you something.

Best fix would be to add proper 30 amp dedicated circuit/outlet to house/garage and eliminate all adapters, plug proper 30 amp RV power directly into outlet. Then determine if you can run one or two heaters without exceeding 30 amp load.

Bart Anderson · 03-21-2017, 04:56 AM

Quote:

Originally Posted by Skrewball

HELLO,

We recently purchased a used 90 H.R. Monitor. We've been tuning our power from an external source but yesterday the plugs melted. We purchased new ones and they are getting warm, it not melting. We also replaces all of our internal breakers with new ones. What is causing this?

Also we finally got our generator running and yesterday near the rear breaker box I kept hearing a relay constantly tripping. Could this become an issue?

Yes i agree too many amps for the 20 amp ckt and or bad connections

Sweetbriar · 03-21-2017, 04:56 AM

Three portable electric heaters will slowly overheat the extension cord and burn out the plug. You need to either reduce the power demand or get a bigger cord.

A little math helps also to keep you out of trouble. Power conversion (aka Ohms Law) is pretty simple to figure out your energy usage and potential demand. If you know two of the numbers you can figure out the third -
Watts = Volts x Amps or
Amps = Watts / Volts
There's a bit more to it but voltage for our applications is static at around 120VAC or 12VDC. If you know two of the numbers you can find the third. The electric heaters should have a tag that will list usually list the maximum volts and watts. If for example all three are 1000 Watts at 120VAC each require 8.3 Amps when going at full blast. All three will added together and you have the potential of just under 25 amps of demand. Not enough to trip a 30 amp breaker but enough to burn out a shop extension cord extension cord.

Waiter21 · 03-21-2017, 05:55 AM

Older plugs get a little corroded and the springy contacts don't make as good as they used to. This makes for a bad connection.

Then when you start drawing a lot of current through the less than perfect connection, it gets hot and makes the connection even worst. Over time, the results are what you see., a burnt connector.

An Ounce of Prevention:

I always inspect the connectors on the end of my power cord before using them. If they are a little corroded or arc/pitted, I use a green pad to clean them up a little. Also once a year or so, take the connector apart and check the screws that hold the wires to the connector blades to make sure they are tight.

If the connector has any burning or pitting on the blades, consider replacing the connector.

The connector on my New-to-Me Southwind has some serious arcing / pitting. I'll be replacing it before we hit the road.

ALSO - When I plug into a pedestal and it feels abnormally lose, I'll usually get my 50 to 30 adapter out and plug into the 50 amp. But connectors on the pedestal will damage your connector.