RCMAN46 wrote:
The 220VAC is two phase power with each leg 180 degrees from each other.
Excellent visual for the lay person(even if there are some technicalities).
If you tie Phase 1 back to the common, you get 120v.
If you tie Phase 2 back to the common, you get 120v.
If you tie Phase 1 to Phase 2, you get 240v.
Generally in an RV, Phase 1 & 2 are only tied back to the common, so you wind up with 50amps @ 120v on each Phase (aka: Leg).
ScottG wrote:dougrainer wrote:RCMAN46 wrote:
The 50 amp 220 volt is the same as the 30 amp 220 volts at your home.
Most RV's loads are 110 volts thus only use one side of the 220 volts as do most of the loads at your home. Most homes only the water heater, electric range and electric furnace use 220 volts and most are 30 amps or less with the exception of some heat pumps. A heat pump in a RV may be wired for 220 volts.
NO HP in a RV is wired for 220 volts. No such HP for an RV has 220 volts. ALL are 110 volts.
220/240 volts in an RV is supplied by 2 separate 120 wires OUT OF PHASE. EACH side is on a 50 amp breaker for 100 amps total supply. The RV does NOT separate the supply. The supply is already separated at the POLE. If the Supply is in phase, the RV will not function correctly all the time. For instance, you have a built in EMS (energy management system) . IT sees if the supply is out of phase. IF IT IS, then you have full 100 amp capacity. IF same phase at supply the EMS will only allow 30 amps total operation. It assumes you have connected a 50 to 30 amp reducer dogbone. IF you think you are connected to a 50 amp service and your EMS shows 30 amp, you have what I call CHEATED 50 amp service. The RV park did not upgrade their supply and wiring for true 50 amp total 100 amp service. This is theft by the RV park. You are paying for 50 amp service and they are NOT giving you what you pay for. The simple test ALL RV'ers need to do is have a multitester and at the Park Pole test the voltage between the 3 and 9 o clock spade slots. 50 amp will show 240. ANY OTHER reading, the pole is NOT 50 amp. Doug
A good explanation. Only thing wrong with it is that the "out of phase" part - a common misconception.
They (the two legs) are in-phase with each other and maybe easier to understand as two halves of the same phase. On an oscilloscope the signal would look like one complete sine wave. That phase is then split into the two, 120VAC legs.
So your 240VAC service is referred to as Split-Phase.
The 220VAC is two phase power with each leg 180 degrees from each other.
AllegroD wrote:
A link and pic as sometimes the visual helps.
RV 50amp
More reading
One thing the pic provides is how your RV handles L1 & L2, at the RV distribution panel. You can, therefore, audit what is wired to each leg, such as ACs, inverters/chargers, and 110 plugs, in case you wish to use high load items, such as space heaters.
Well you can access a 30 amp 240 volt circuit in an RV with a 50 amp service with a breaker like in the link. It would replace the 50 amp main. This allows us too have the cheap heat electric add-on heating to our gas furnace.
50/30 amp Quadplex breaker
