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Truk,
I am no electrician but if you want 50 amps, then a 50 amp breaker is your protection, not 60. # 6 wire is code in CA for 50 amps, I think and depending on the distance you might loose a little. You should have 50 amps on both legs as long as the electrician wired you into 220, if not find a new one!
Kevin is correct. We have been over this before, but to make it clear a campground power outlet box typically has three receptacles.
The 20 amp and 30 amp recaptacles are 20 and 30 amp at 120 volts. That is the total amperage.
The 50 amp receptacle is a misnomer. It is actually two 50 amp legs at 120 volts for a total of 100 amps at 120.
In Tom's case he could run the devices he wants and still run his electric heater off his forward or rear outlet circuits. That assumes the electrician did give him a 50 amp RV type receptacle. To verify what he has he should have a 50 amp double pole breaker in his panel for that RV receptacle. If that is the case there is no need to run the heater from another source.
I agree with the bay heater being an industrial heat gun. I also do not use it for several reasons. On my coach it is a high wattage current draw. If I needed heat I would rather use a 500 watt setting on a small cube heater. I don't like the fact it is either spewing out a lot of heat, or it is off depending on the need. I would rather have a small continuous heat source that is quieter and concentrated on keeping the big water holding tank warm. When the tank is warm it will protect the bay in even the worst temperatures.
Jim, why suggest 60 amps? Nothing is rated for that amperage, including the receptacles, the wires, or the plugs.
Kevin - I had wired the whole garage myself and put a 30 amp in for RV. After getting the first bus, it was obvious I needed 50. So I hired this guy to come out and help me run 220 to the new 50 amp bus plug I had ready, cause I'm too whimpy to struggle pulling that big wire while doing a goose walk in the trusses of the garage. I gave him a call today and he apologized for telling me it's two legs of 25, when in fact it's 2 legs of 50, just like the Campgrounds. I put 400 amp in the house when I built it and a 100 amp sub panel for the garage, so I have lots of juice.
So just for fun, I loaded the ole girl up with 2 heat pumps cranking along with the water heater and 41 amps on one leg was no problem. Now I know and the heater is running off the bus.
Jon - I called it a hair dryer cause I knew Jimmy C would have a cow.:p He's probably sitting in front of the computer right now in his jammies looking at pictures of Key West and not wanting to look out his window. That Liberty heater is probably a good one, but just like you said, it's either off or on and I don't trust it while not staying in the bus.
Sorry. No. Current is the same everywhere in a loop, unless you have a current leak somewhere to ground or neutral, in which case you have other (and serious) problems. Voltage drop occurs over distance, however, and that can be a problem (addressed with a given minimum wire size). Again, if you have 50A at the panel, you have 50A at the other end of the cable unless there is a fault to ground somewhere in between. And in that event, especially, you do not want a breaker rated higher than the (system) current you will safely and normally require, within the rated limits of the system.Quote:
Originally Posted by JIM CHALOUPKA
Thanks for listening.
While working on the Bus today it was sitting outside the garage with the sun shining on it. The inside temp got hot enough I had to turn on the A.C.
I was trying to convey without going into detail that the breaker that one usually purchases with the 50A rating is by the NEC rating only going to work at 80% of that number, or 40A. This comes from the fact that the breaker is rated in free air @ 40C to 50C degrees, and will under those circumstances handle the 50A rating, but when in practical application they are enclosed in a cabinet/box they only perform at 80%. If one wants the 50A he needs to use a breaker labeled SP (supplementary protector), which functions at 100% of its rating. These are not as easy to find.
The plug and wire as are rated for 50A and will therefore safely carry the load protected by a 60A breaker which at 80% will protect 48A.
JIM
I don't want to pretend I know it all but I won't exceed 50 amp breakers on #6 wire . There are certain exceptions, but is with specific connected load not general purpose. Also, in most RV parks the wiring of the pedestals are typically wired in Parrallell (2 to 4 - 50 amp Pedestals) on one 100 amp sub feed. Meaning, you don't really have 50 amp capability if 2-3 others are drawing heavy loads at the same time.
Jim, if a 50A power outlet will only give out 80%, the power would be 46A instead of 48A. There goes those percentages. It is different if you took math in Tennessee.
Jim, if a 50A power outlet will only give out 80%, the power would be 40A instead of 48A. There goes those percentages. It is different if you took math in Tennessee.
Country Coach runs all of their 110V power (outlets only) thru the coach after it goes through a GFI, believe a 15 amp GFI but it may well be a 20. There is your answer.:p
John