Plugged into 120 volt... What can I run?

[Plasma800]

I just moved and have yet to run a full 30 amp circuit.

But I'm curious, if I'm stepped down to 120 volt, typical house circuit from an extension cord, what can I run?

Obviously the Ac unit is out of the question, but it seems I should be able to operate all lights, fans, tv.

Fridge on Ac?
Heater?
Electric blanket?

I ask cause I have a bunch of guests over New Years and I wanted to let a couple sleep in it, but it will be cold that night.

[lewster]

Originally Posted by Plasma800

I just moved and have yet to run a full 30 amp circuit.

But I'm curious, if I'm stepped down to 120 volt, typical house circuit from an extension cord, what can I run?

Obviously the Ac unit is out of the question, but it seems I should be able to operate all lights, fans, tv.

Fridge on Ac?
Heater?
Electric blanket?

I ask cause I have a bunch of guests over New Years and I wanted to let a couple sleep in it, but it will be cold that night.

30 amp IS 120VAC. If your question is actually what can you operate from a 'standard' 15A or 20A household circuit, you are limited! Your power converter will provide all of your 12VDC electrical needs like running all of your control boards, lights, furnace blower, etc. I would suggest keeping the 'Use/Store' switch located at your entry door to 'Store' so your single stage converter does not overcharge your battery.

I would look at the breaker rating of the outlet feeding your trailer to see if it's 15A or 20A, as it will determine what else your can operate; fridge on 120VAC plus water heater on electric……..probably……….throw in an electric blanket…….you're pushing it or over the circuit's rating.

Not knowing the actual breaker rating, it's hard to tell what the total of appliances' wattage is available. Remember that 15A @ 120VAC is 1800 watts, and 20A @ 120VAC is 2400 watts. Your fridge element is around 400 watts, water heater is 1500 watts and the converter wide open should be around 750-1000 watts.

Start adding and you see that you don't have all that much head room for operating your LP appliances on 120VAC.

[nvestysly]

Let me start by saying 30A for an RV is 120V. The voltage is not what's different - the current (amps) is what's different depending on what type of outlet you are connected to.

Typical household outlets in the U.S. are 15A. Some outlets are 20A and they look very similar to a 15A outlet - most people wouldn't know the difference between 15A and 20A. I've included pictures below. Notice the 20A has a T shape on one of the contacts. Your plug won't have a T shape so don't worry about that.

Assuming you are connected to a 15A outlet you can certainly run a space heater, the frig on AC, turn on some lights - probably not more than that.
The electric blanket may be fine with the frig on AC and some lights but turn on a space heater and that's probably too much. The blanket, frig on AC, some lights and the furnace are probably okay.

If the outlet happens to be a 20A you probably won't have a problem running a variety of electrical devices at the same time. A space heater and the microwave may cause a problem but other than that - frig on AC, furnace, etc. likely not a problem.

Each trailer varies and there are so many other factors. Even though an outlet is rated at 15A you may have other things (in your house) on that same circuit. You can see why it's not an entirely clear-cut answer.

(on edit - I see Lewster and I were replying at nearly the same time but he's a faster typist! But hey, I included pictures)

[polarlyse]

I can run most things singly but in combination I have trouble with the water heater blowing the breaker in the house. Refrig along with most anything else is OK but if I forget to throw the switch for the water heater ....... ooops. Seems to even work OK with the lights, water pump and heat so long as the water is on propane only. My son and family used it for showers after hurricane Sandy for a few weeks. If in doubt sit down and just add up the amps and stay below the max for the breaker.

[lewster]

Originally Posted by nvestysly

Let me start by saying 30A for an RV is 120V. The voltage is not what's different - the current (amps) is what's different depending on what type of outlet you are connected to.

Typical household outlets in the U.S. are 15A. Some outlets are 20A and they look very similar to a 15A outlet - most people wouldn't know the difference between 15A and 20A. I've included pictures below. Notice the 20A has a T shape on one of the contacts. Your plug won't have a T shape so don't worry about that.

Assuming you are connected to a 15A outlet you can certainly run a space heater, the frig on AC, turn on some lights - probably not more than that.
The electric blanket may be fine with the frig on AC and some lights but turn on a space heater and that's probably too much. The blanket, frig on AC, some lights and the furnace are probably okay.

If the outlet happens to be a 20A you probably won't have a problem running a variety of electrical devices at the same time. A space heater and the microwave may cause a problem but other than that - frig on AC, furnace, etc. likely not a problem.

Each trailer varies and there are so many other factors. Even though an outlet is rated at 15A you may have other things (in your house) on that same circuit. You can see why it's not an entirely clear-cut answer.

(on edit - I see Lewster and I were replying at nearly the same time but he's a faster typist! But hey, I included pictures)

Yep! Dem fingas was smokin'!!!!! Hope dat outlet ain't smokin'

[Plasma800]

Ok yes I get it.

So they have no need honestly for the fridge, and if so I could run on propane.
They have no need for the microwave, so safe there.
The water heater can run on propane, so no problem there.

Wonder what the fan on the heat draws.

I'll try it out tomorrow and see if it pops my house circuit.

[CRH]

I can plug into the 15A outlets in my garage and run my AC.

[nrgtrakr]

Ditto ... but only on low.

[SCOTTinNJ]

If your outlet at home is gfi protected it will likely pop as soon as you plug the trailer in. You may have to use a non gfi protected outlet.

[MelGoddard]

Originally Posted by Plasma800

I just moved and have yet to run a full 30 amp circuit.

But I'm curious, if I'm stepped down to 120 volt, typical house circuit from an extension cord, what can I run?

Obviously the Ac unit is out of the question, but it seems I should be able to operate all lights, fans, tv.

Fridge on Ac?
Heater?
Electric blanket?

I ask cause I have a bunch of guests over New Years and I wanted to let a couple sleep in it, but it will be cold that night.

With my previous Hi-Lo, and now a 25' 'Cloud', I can run everything except the AC, just as you state.
Two things you need to do:
1/ Get and use an extension cord of at least 12 gauge, or larger if a long 'run'. Plug it into a dedicated house circuit, nothing else on it.
2/ Do your ' electrical load analysis'; don't run everything at once.
- Fridge on AC, and electric blanket, fine; but don't add a toaster and electric coffee pot also; or that heater.
Remember, you have only 15 amps, or 1800+ watts at your disposal. any more will pop your circuit breakers. Check your appliance data plates for the loads.

[MelGoddard]

Originally Posted by lewster

30 amp IS 120VAC. If your question is actually what can you operate from a 'standard' 15A or 20A household circuit, you are limited! Your power converter will provide all of your 12VDC electrical needs like running all of your control boards, lights, furnace blower, etc. I would suggest keeping the 'Use/Store' switch located at your entry door to 'Store' so your single stage converter does not overcharge your battery.

I would look at the breaker rating of the outlet feeding your trailer to see if it's 15A or 20A, as it will determine what else your can operate; fridge on 120VAC plus water heater on electric……..probably……….throw in an electric blanket…….you're pushing it or over the circuit's rating.

Not knowing the actual breaker rating, it's hard to tell what the total of appliances' wattage is available. Remember that 15A @ 120VAC is 1800 watts, and 20A @ 120VAC is 2400 watts. Your fridge element is around 400 watts, water heater is 1500 watts and the converter wide open should be around 750-1000 watts.

Start adding and you see that you don't have all that much head room for operating your LP appliances on 120VAC.

Hey Lew;
Everything that you stated is good information. but; you forgot to add using a 12 gauge extension cord, or larger over 30'.
OOPS!

[lewster]

Originally Posted by MelGoddard

Hey Lew;

Everything that you stated is good information. but; you forgot to add using a 12 gauge extension cord, or larger over 30'.

OOPS!

I didn't because it should be 10 AWG for longer runs. My 12AWG cords are limited to 20', 10 AWG over that.


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
ABYC Certified Master Marine Electrician
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center*AMS Lithium Batteries
Lifeline AGM Batteries**Magnum Inverters
541-490-6357

[DKB_SATX]

Originally Posted by Plasma800

Ok yes I get it.

So they have no need honestly for the fridge, and if so I could run on propane.
They have no need for the microwave, so safe there.
The water heater can run on propane, so no problem there.

Wonder what the fan on the heat draws.

I'll try it out tomorrow and see if it pops my house circuit.

If you're running just the propane furnace, the fan is 12v DC and will run fine with just the converter and/or batteries powering it while you're plugged in.

If you're running a resistive heat strip in an AC unit and nothing else, I think it would run OK but if you have a long run of extension cord it'll heat up, the strip itself is about 1500W plus the fan load. If you're thinking of running a heat pump, just don't. If you have a recent "CCC" thermostat and a heat pump I think you should set the mode to furnace-only for heating when plugged into a 15A or 20A circuit.

[dkottum]

A utility extension cord is simply an inadequate carrier for Airstream power, outside of lights, tv, radio, converter/charger, furnace (no heat pump), and maybe the fridge (which will automatically choose 120v operation with external power). If too much is turned on (innocently) and the extension cord is too long or too small, there is a good chance of voltage drop which could damage the Airstream's equipment. If you plug it into a GFIC household circuit, the household circuit breaker will trip.

You could run a separate cord out for a space heater to directly plug into. Not sure where there is an opening to get it inside the trailer.

[Rich W]

Originally Posted by nvestysly

[snip]

Typical household outlets in the U.S. are 15A. Some outlets are 20A and they look very similar to a 15A outlet - most people wouldn't know the difference between 15A and 20A. I've included pictures below. Notice the 20A has a T shape on one of the contacts. Your plug won't have a T shape so don't worry about that.

I have a question. In my home I have 20 amp breakers but the outlets don't have the T shape. Is the T shape for a dedicated 20 amp outlet, no other outlets on the same circuit, or did my contractor just not provide them?

[kscherzi]

Same here. The garage is wired for 20 amps yet the plugs look normal (no T). BTW. I've run the water heater on electric and a space heater at the same time. Turn on the microwave and the circuit pops. No big deal. Just reset the breaker and turn one of the other appliances off.

[nvestysly]

Originally Posted by richw46

I have a question. In my home I have 20 amp breakers but the outlets don't have the T shape. Is the T shape for a dedicated 20 amp outlet, no other outlets on the same circuit, or did my contractor just not provide them?

Originally Posted by kscherzi

Same here. The garage is wired for 20 amps yet the plugs look normal (no T). BTW. I've run the water heater on electric and a space heater at the same time. Turn on the microwave and the circuit pops. No big deal. Just reset the breaker and turn one of the other appliances off.

That's a good question and I don't know the answer. I hope somebody with more experience will chime in.

I installed two circuits in our house that needed to be 20A dedicated circuits. One for a large air compressor and one for a basement sump pump. In both cases the breaker is rated at 20A and the outlet is the T shape. Don't know if that's overkill or not.

Looking at the existing circuits in my breaker box I see a variety of 15 and 20 amp breaker switches with no apparent rhyme or reason as to the rating. All the other circuits (except the dedicated circuits) serve a variety of wall outlets and ceiling lights.

Back to the 15A outlets common in most houses. There are usually several outlets on the same circuit. You can't really draw 15A from every outlet.

[markdoane]

Originally Posted by nvestysly

Back to the 15A outlets common in most houses. There are usually several outlets on the same circuit. You can't really draw 15A from every outlet.

This is pretty close to the correct answer. When there are multiple outlets on a 20a branch circuit then 15a outlets are OK.

It's not the receptacle that is important in this case. It's the plug that goes into the receptacle. If the device that plugs into the receptacle is rated at 20a, then it will have one prong at right angles so it will only go into a 20a rated receptacle. But the same receptacle is also able to accept any lower rated 15a appliances.

[TG Twinkie]

It has to do with $$$$$. 15 amp outlets are less expensive than 20 amp outlets. In 99% of the time 15 amp outlets are fine.
Not sure how the electrical inspectors let the installers get by with installing 15 amp equipment on a 20 amp circuit.
Circuit breakers are sized to protect the wire and installed devices such as outlets. Not what is plugged into those outlets.
If you have a 15 amp outlet connected to a 20 amp circuit breaker and that outlet is drawing 18 amps because of whatever is plugged in. The outlet will probably overheat and may cause a fire. IMHO

[markdoane]

Originally Posted by TG Twinkie

Not sure how the electrical inspectors let the installers get by with installing 15 amp equipment on a 20 amp circuit.
Circuit breakers are sized to protect the wire and installed devices such as outlets. Not what is plugged into those outlets.
If you have a 15 amp outlet connected to a 20 amp circuit breaker and that outlet is drawing 18 amps because of whatever is plugged in. The outlet will probably overheat and may cause a fire. IMHO

Electrical inspectors let installers get by with it because Code allows it.

Circuit breakers are sized to protect the wire and installed devices. And the outlet is rated for 20a passthrough. Even though the outlet is called a "15a Duplex Outlet", the internal connections are sized to handle 20 amps. A properly installed outlet will not overheat and cause a fire.

If you have two 9a appliances plugged into a 15a duplex outlet, the outlet will be fine if it is connected to a 20a breaker with the correct size wire.