Where ever you hook up a motorhome see's a 50 amp plug as 2 separate 110 leads.
Whether you are plugged into a 50amp plug that has 220vac potential (2 110 lines out of phase with each other) or the less common 50 amp plug that is 2 110vac lines that are the same phase, your RV only uses it as 2 110 vac lines.
The "50 amp cheater box" is not cheating anything, it is using the 30amp 110vac line for 1 line and the smaller outlet which is usually ran through a 20 amp breaker at most camp sites you are getting the same power to your coach, somes times it might only be 30 amp on 1 side and 15 on the other it is still much better than using a 30-50 adapter plug because it is actually putting the voltage from the 30 amp plug to both input lines into the coach.
hope this helps
we use ours quite often. you need to know how the rig is wired. it takes time to figure which leg to make the 30 and the other the 15. we have to turn off the hot water heater when we use the microwave. we cannot use the washer and the 2nd air at the same time.
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stevelv wrote: So what exactly do I have now - do I have 30amps on one circuit and 15amps on the other or do I have 45 amps across all circuits.
Normally, when plugged into a 50 amp pedestal, you would have 50 amps available on leg A feeding half your circuits, and 50 amps available on leg B feeding the other half of your circuits. This gives you a total of 12,000 watts available. (50 * 120) + (50 * 120)
With the cheater box, you will have 30 amps on one leg feeding half your circuits, and 15 amps on the other leg feeding the other half of your circuits. Which half is which depends on how the cheater box and your electrical panel is wired up. You can use 30 amps on one half, and 15 amps on the other half, but you can't use 45 amps on only one half. This gives you a total of 5,400 watts (30 * 120) + (15 * 120)
When you are using a 30 to 50 amp adapter, the single 30 amp line is connected to both of your hot legs, so you have a total of 30 amps shared between both hots. You can use 30 amps on leg A, and nothing on leg B; or you can use nothing on leg A and all 30 amps on leg B; or you can use some on leg A and the rest on leg B, as long as the total doesn't go over 30. This gives you a total of 3,600 watts (30 * 120)
So, with the cheater box, you can have more power available than with the 30 amp adapter, but it is not divided arbitrarily among loads as it is with the adapter.
You will have to do a little bit of work to figure out what you can run at one time. The first thing you need to do is look at your AC breaker box. It is normally pretty easy to see which circuits are on each leg (hopefully it's labeled!) Then, unplug the 15 amp plug, leaving only the 30 amp plug connected, and check to see which circuits have power and which don't. This will tell you which leg is which, as the circuits that have power are on the 30 amp side, and the ones that don't are on the 15 amp side.
After plugging in the 15 amp circuit again, now all you have to do is make sure you don't go over 30 amps (3,600 watts) on the 30 amp side, and 15 amps (1,800 watts) on the other side. You will have to look at the rating plates of your various loads and add them up to figure out how many you can run at once on each leg.
If you have an energy management system (EMS) that tracks loads for you, and shuts off certain loads as needed (like the water heater and an air conditioner) so that you don't go over your rating, it will likely be confused by the cheater box, and will either not limit your power consumption for you, or will limit your total power usage to less than you have. This is because if the two circuits you connected to are on opposite legs of the campground supply, the EMS will think you are on a 50 amp circuit, and will assume you have 12,000 watts to work with, and will not hold you to your 5,400 watt budget. But if the two outlets are on the same leg, it will think you are on a 20 or 30 amp circuit, and will only let you use 2,400 or 3,600 watts of the available 5,400 watts. You see, using a cheater box results in a non-standard electrical supply, and is something that the EMS is not designed to handle.
Hopefully this makes sense to you. It's complicated enough that it's hard to explain concisely.
Edit: looks like I took too long typing, as others have beat me to the punch. Sorry for any duplication of information.
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robertmeier wrote: we use ours quite often. you need to know how the rig is wired. it takes time to figure which leg to make the 30 and the other the 15. we have to turn off the hot water heater when we use the microwave. we cannot use the washer and the 2nd air at the same time.
If yours worked properly, you shouldn't have to turn off anything.
It's what I expected but just needed it confirmed. Looking at the box I see it actually has 2 30amp circuits (one had a 15amp adaptor on it) and the pedastal has 2 30amp outlets and so I can use 30 + 30 which should work fine - I just need to do a polarity check on the other 30amp.
I assume that there is no problems if the second 30amp is on a different phase?? No GFCI to worry about.
The campground originally had the space that I take up divided into 2 sites, for smaller TTs and they then converted it to one long pull through - however the pedastal was never converted to 50amp and still has the 2 30amp outlets - the campground circuits are designed to feed two TTs at 30amps and so they are OK with me using the 'cheater' box.
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