Oopsie !

[Stranger]

Ok, here's the deal. We moved from California to Indiana. Went to plug the Alfa into the house. The dryer plug in the house is 2 blades at 90 degrees forming a point above a "L" shaped opening.



I changed that to an RV type plug. 2 blades at 90 degrees over a round opening.



Smoked the satellite receiver box, literally. TV doesn't work, microwave is also toes up. Replaced the M/W and power convertor. Waiting for the after XMAS sales for the TV.



My questions are;

1. ) Where are the fuses that should protect the refer, Dometic 8 ft'er? Is it readily accessible?

2. ) Same thing for the RCA TV?



Thanks.

P. S. You can stop laughing now.

 

[Jumbo Jet]

Dryer plug is 220 Volts. Alpha most likely should be 120 Volts according to the plug you are describing 120 Volt 30 Amp.



Pastor of my church had his RV plug wired by an electrician - the electrician wired it for two hots - 220-240 Volts. Burned up the microwave, TV. The A/C had not been wired, so he saved that.



You will need to check every appliance that is connected. A/C - Water heater if it has a "hot rod". AC to DC Converter. Etc.



Outlets are all on breakers behind the Converter panel - most likely.

 

[JApol]

NOt to hijack or anything but when I was a senior in high school, the school has just opened the new metal/auto shop. I plugged in a drill and it started spinning REAL fast. Unplugged the drill and plugged in a multimeter. Sure enough 220 on a 110 plug.

 

[Nate]

240 volts on a 120 2 prong plus isn't that uncommon for farm use. Normally the wall plate is red.

 

[JApol]

but this was one of those retractable types hanging from the ceiling. If i remember right the plug was yellow. What has a 120 plug and uses 240 anyway.



P. S. My appologies stranger

 

[Slow Six]

You will need to get that unit completely checked out. You applied double the voltage that the unit is designed for. Breakers really don't protect from over voltage, they are for overload. Fridge breaker should be on the main panel with other breakers and/or fuses. Sorry for your incident but these things happen and it sounds like no one was hurt or no serious damage like a fire.

 

[Nate]

You know, I'm not too sure what actually used it, I think it was older machinery. I haven't seen it in newer farm buildings.



I do know an old 1960s 120volt air compressor pumps air very fast at 240volts and will make my Dad run to see what the hell is going on.



Getting back on the thread... I've never seen a 240v plug only having 120volts... definately a costly deerrrrrrrr de derrrrr for that camper.

but this was one of those retractable types hanging from the ceiling. If i remember right the plug was yellow. What has a 120 plug and uses 240 anyway.



P. S. My appologies stranger

 

[DIESELMAN]

WARNING!!! If you purchase the outdoor RV Power Outlet Box from Home Depot, look inside the lid, it shows BOTH blades as LINE!



This box is distributed by Connecticut Electric, the box is made in China and the outlet made in Mexico. IT DOES CARRY A UL Stamp, but it is junk. The ground screw is marked ground, however, BOTH BLADE SCREWS ARE SILVER! NEITHER IS MARKED WITH W or N, or X or Y - NOTHING!



If you hook it as shown on the label you can be KILLED! Your Chassis will be HOT - 120V to Ground if the ground lead fails or if the breaker fails to open!



Your RV will also be at 240V! Goodbye Appliances!



It should be noted that the plugs for RV's are designed for specific use. The plugs that are 50 AMP (found on newer/larger RVs) are NEMA rated 14-50P (plug) and plug into a 14-50R (receptacle). The 30 AMP plug combination does not combine with the 50 AMP plug. The 30 AMP is a standard (ANSI C73. 13) or NEMA TT-30P (plug) / TT-30R (receptacle).



UL LISTED sockets are marked G for the Ground, the round or 'U' shaped pin, and W or N on the Silver screw for Nuetral, the Hot lead is usually not marked but will usually have a Brass screw, it may also be marked B or X or Y.



But back to the Home Depot box, Don't buy junk even if you know how to wire it correctly, this just supports shoddy marketing ala Wal-Mart.

 

[robertyoke]

WARNING!!! If you purchase the outdoor RV Power Outlet Box from Home Depot, look inside the lid, it shows BOTH blades as LINE!



This box is distributed by Connecticut Electric, the box is made in China and the outlet made in Mexico. IT DOES CARRY A UL Stamp, but it is junk. The ground screw is marked ground, however, BOTH BLADE SCREWS ARE SILVER! NEITHER IS MARKED WITH W or N, or X or Y - NOTHING!



If you hook it as shown on the label you can be KILLED! Your Chassis will be HOT - 120V to Ground if the ground lead fails or if the breaker fails to open!



Your RV will also be at 240V! Goodbye Appliances!



It should be noted that the plugs for RV's are designed for specific use. The plugs that are 50 AMP (found on newer/larger RVs) are NEMA rated 14-50P (plug) and plug into a 14-50R (receptacle). The 30 AMP plug combination does not combine with the 50 AMP plug. The 30 AMP is a standard (ANSI C73. 13) or NEMA TT-30P (plug) / TT-30R (receptacle).



UL LISTED sockets are marked G for the Ground, the round or 'U' shaped pin, and W or N on the Silver screw for Nuetral, the Hot lead is usually not marked but will usually have a Brass screw, it may also be marked B or X or Y.



But back to the Home Depot box, Don't buy junk even if you know how to wire it correctly, this just supports shoddy marketing ala Wal-Mart.

so dieselman is the 50 amp plug on the new stuff just using one leg (50a @120v) or are both legs hot (50a @240v) ?? I have never pluged in at a camp ground and have never checked the voltage.

-robert

 

[RustyJC]

120/240VAC 50A RV service uses 4 conductors. The 2 line conductors must be 180 degrees out of phase. The other 2 conductors are neutral and an isolated ground (i. e. , neutral is NOT tied to the ground bus on the RV side of the plug). This means that a voltmeter check of the plug will show 240VAC between the hot legs and 120VAC between either hot leg to neutral if the plug is wired correctly. Each of the hot legs has the capacity for 120VAC 50A (2 each 50A circuit breakers, right?), so the total theoretical ampacity of a 120/240VAC 50A RV circuit is 100A.



In order to take advantage of campgrounds that don't have 50A service, almost all RVs are wired with 2 independent 120VAC 50A buses in the power distribution panel. No appliances in these RVs use 240VAC, which isn't available if the RV is plugged into 30A or lower service at the campground or RV park.



Rusty

 

[JStraw]

Guy I'm confused.



When I wired my box to connect the rig, I utilized 120 volts on a 50 amp circuit. One leg to black wire, one leg to white (neutral) wire, and the ground. Half of the trailer worked and the other half was dead. When I rewired both legs to seperate 120 volt 50 amp breakers everything worked great. Black wire hot w/CB, white wire hot w/ seperate CB, and the ground. Is it now considered 240 volt or 120 with 2 seperate legs and breakers?

 

[RustyJC]

Take your voltmeter and check between the 2 hot legs at the shore power receptacle. If you have 240VAC, then it's wired correctly for 120/240AC 50A RV service (assuming the neutral and ground are correct. ) If you have 0VAC, then you have a potential problem.



With the hot legs 180 degrees out of phase (as they should be - 240VAC reading), the neutral leg current is the difference between the 2 hot leg currents (example: 40A on one leg, 35A on the other leg equals 40A - 35A = 5A neutral leg current. )



With the hot legs in phase (0VAC reading), the neutral leg current is the sum of the 2 hot leg currents (example: 40A on one leg, 35A on the other leg equals 40A + 35A = 75A neutral leg current. ) Since the 50A RV power cord conductors are sized for 50A, this situation can overload the neutral conductor in the power cord.



Rusty

 

[MCrossley]

Yes, and this is why if you do not understand how to do it correctly you should hire an electrician... Period! I hate people that try to do something that they have no idea how to do with electricity, I have fixed so many "little" issues that could have killed someone very easily, working on our trucks is one thing wiring a service that can not only kill you but burn something to the ground is better left to those who know how to do it... . Not trying to flame anyone just making a point.

WARNING!!! If you purchase the outdoor RV Power Outlet Box from Home Depot, look inside the lid, it shows BOTH blades as LINE!



This box is distributed by Connecticut Electric, the box is made in China and the outlet made in Mexico. IT DOES CARRY A UL Stamp, but it is junk. The ground screw is marked ground, however, BOTH BLADE SCREWS ARE SILVER! NEITHER IS MARKED WITH W or N, or X or Y - NOTHING!



If you hook it as shown on the label you can be KILLED! Your Chassis will be HOT - 120V to Ground if the ground lead fails or if the breaker fails to open!



Your RV will also be at 240V! Goodbye Appliances!



It should be noted that the plugs for RV's are designed for specific use. The plugs that are 50 AMP (found on newer/larger RVs) are NEMA rated 14-50P (plug) and plug into a 14-50R (receptacle). The 30 AMP plug combination does not combine with the 50 AMP plug. The 30 AMP is a standard (ANSI C73. 13) or NEMA TT-30P (plug) / TT-30R (receptacle).



UL LISTED sockets are marked G for the Ground, the round or 'U' shaped pin, and W or N on the Silver screw for Nuetral, the Hot lead is usually not marked but will usually have a Brass screw, it may also be marked B or X or Y.



But back to the Home Depot box, Don't buy junk even if you know how to wire it correctly, this just supports shoddy marketing ala Wal-Mart.

 

[robertyoke]

Take your voltmeter and check between the 2 hot legs at the shore power receptacle. If you have 240VAC, then it's wired correctly for 120/240AC 50A RV service (assuming the neutral and ground are correct. ) If you have 0VAC, then you have a potential problem.



With the hot legs 180 degrees out of phase (as they should be - 240VAC reading), the neutral leg current is the difference between the 2 hot leg currents (example: 40A on one leg, 35A on the other leg equals 40A - 35A = 5A neutral leg current. )



With the hot legs in phase (0VAC reading), the neutral leg current is the sum of the 2 hot leg currents (example: 40A on one leg, 35A on the other leg equals 40A + 35A = 75A neutral leg current. ) Since the 50A RV power cord conductors are sized for 50A, this situation can overload the neutral conductor in the power cord.



Rusty

what in the rv is 240v?? I dont have anything that is 240v. I asked an electrican and he did not now how rv shore power was wired he thought just like any temporary power supply.

120v @ 50 amps is a lot of power and I wonder if the one leg of the 240 v 50a is just not used in my camper. It was an up grade from 30 amp service. if I plug into my 30a plug with my adapter everthing works fine.

 

[RustyJC]

I didn't say anything in the RV is 240VAC, did I? You should have 2 independent 120VAC 50A buses in your RV's power distribution panel (you do have 2 each 50A circuit breakers tied together, right?) The 240VAC is a result of these buses being 180 degrees out of phase.



In fact, these 2 independent buses are jumpered together and powered as a single 120VAC 30A bus when you use an adapter and plug into, let's say, a 30A shore power receptacle.



Rusty

 

[robertyoke]

. all is good, I just thought that the 50a plug was diffrent for a camper than home use. I never looked to see if the panel had a disconnect. and I never checked to see if the adapter split the 30a to feed both legs of the 50a cord ( i thought it didn't). I thought that maybe campers have thier own set of rules but it is the same as home use. now i see said the blind man!

-robert

 

[DIESELMAN]

To sum it up, good thread BTW, 30A Service means that the total current available is 30A, there is one ground, tied to the chassis, one neutral, and one hot, hot to neutral is 120V.



You should NOT have the ground tied to the Neutral, UNLESS, you have a generator or real inverter, then, the transfer switch should open neutral to ground on shore power (plugged in at home or park) yet bond them together when under inverter or generator power (and it should open the shore lines, ground, neutral and hot).



Cheap generators and some cheap inverters bond the Neutral and Ground, this can result in current flow through the chassis when on shore power.



Now 50A Service REQUIRES a 240V feed, that is BOTH hot legs, L1 and L2, which are out of phase with each other, yet, because it feeds half on one leg and half on the other, the maximum neutral current is only 25A. Most RV's have nothing that is operating on 240V, though they could.



There are many different 50A to 30A converters, which should only be used if you do not have any 240V appliances (thats 99% of you), they work by powering only L1 or L2, which means half your stuff won't work, or they tie both L1 and L2 together, which actually violates UL and NEC code, and isn't good for 240V stuff (that 1% of you, and me. ).



The best way is to use what is called an Autoformer, a transformer that balaces loads between the two legs, and can power an unpowered leg from the powered leg, keep in mind, this requires wiring upgrades, proper switching in the transfer switch, and attention to the overall load when operating from a 30A feed. It also allows a 120V generator to power both legs.

 

[MChildress]

My neighbor that had just bought his first RV trailer came down the other day and advised me he had ran 220 into his trailer. I asked what all he burned up and he replied the tv,microwave,and a clock he had plugged in. He told me another neighbor had looked at his trailer plug and told him he needed a 220 30 amp breaker to run to his trailer at his house,so he ran it. My question to him was to think about it ,what do you have in the trailer that runs on 220.

I do have a Miller portable welder that is a 10,000 watt generator. I have made a double pig tail off the 220 plug to two 30 amp 120 plugs. We use to run two trailers in remote areas. I might be causing some of the confusion with these trailers plugged into a 220 plug.

 

[RustyJC]

Now 50A Service REQUIRES a 240V feed, that is BOTH hot legs, L1 and L2, which are out of phase with each other, yet, because it feeds half on one leg and half on the other, the maximum neutral current is only 25A.

Just a minor correction. 120/240VAC 50A service has 2 each buses, each of which has a 50A circuit breaker - the 2 50A breakers are tied together mechanically. Total theoretical ampacity is 2 x 50A, or 100A if each bus were drawing its maximum current capacity. If one bus were at maximum capacity and the other bus were drawing nothing, then the current on L1 would be 50A, L2 would be 0A and N would be 50A - this highly unlikely situation would produce the maximum current on the neutral leg.



Rusty

 

[DIESELMAN]

Just a minor correction. 120/240VAC 50A service has 2 each buses, each of which has a 50A circuit breaker - the 2 50A breakers are tied together mechanically. Total theoretical ampacity is 2 x 50A, or 100A if each bus were drawing its maximum current capacity. If one bus were at maximum capacity and the other bus were drawing nothing, then the current on L1 would be 50A, L2 would be 0A and N would be 50A - this highly unlikely situation would produce the maximum current on the neutral leg.



Rusty

Thats right. The maximum nuetral current would still only be 50A so the circuit is still 50A, L1 and L2 are 180 out of phase, when L1 is max, L2 is at minimum.



Yes, the breakers are barred so if one side trips, the other side is opened. Just in case someone thinks you mean both sides of the breaker are electrically common, they aren't.



RV Power Cables and connectors aren't rated for 100A, so its a bad, though unlikely idea, to run both sides on L1 at max load, but then these 50/30 adapters are usually plugged into a 15/20/25/30A 120V circuit, so it just wouldn't happen anyway.



25A was a brain fart, I have no idea why I typed 25A last post????