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Electrical question
Yahoo Message Number: 96612
We spent the last couple of days driveway camping and used an adapter to plug in since they have no 30 amp hookup.
 We also have a Progressive surge protector. I don't recall the model but it is built in and when you plug in does not let the AC through until it determines it to be safe.

So we found that when we tried to run the heat strip in the AC this would shut it down. Same thing happened when Gayle plugged in her hair dryer. We did not have them running at the same time.
 I thought we could run these type of items in this situation. Is there some way around this?

Jim C
Re: Electrical question
Reply #1 –
Yahoo Message Number: 96613
Depends entirely upon the circuit capacity of the circuit you are plugged into.  If it is an outside outlet it is very likely a 15-amp outlet, and many outlets could be on that same circuit.  At our house, all the outside outlets, all the garage outlets, and all the outlets in a storage room off the garage are on the same 15-amp circuit.  In addition, these outlets are completely on the other side of the house from the power panel.  I can run small things, but something like an air compressor blows the breaker immediately.  Needless to say, the guy that wired this house should be shot.
 Just remember that on a 15-amp circuit the maximum wattage that can run at the same time is a little over 1,500 watts (Technically 1,800 watts at 120VAC, but don't count on that high a voltage.)  That assumes no voltage drop in the line to the outlet you are using.  See if you can find a 20-amp circuit to plug into.  In our case, that is an outlet in the garage for a built-in vacuum that has its own circuit.  I "borrow" it for other uses from time to time.  There is good reason for motorhomes to use a 30-amp circuit for the 120VAC input.

Dick Dewey Arizona
Re: Electrical question
Reply #2 –
Yahoo Message Number: 96614
Jim,

Assuming you are plugged in directly into a power outlet, you have marginal power availability at that outlet.  Perhaps it's 15 Amp service at it and a long way from the distribution box.  With heavy current use your voltage drops below 105 Volts and your surge protector cuts you off.  The LD converter is probably drawing some power to begin with and the additional load of a strip heater or hair dryer takes it over the limit.

Given that the power outlet is safe, as evidenced by the fact the power in the rig is OK before you turn on a heavy load, you can try skipping the surge protector.  The voltage will still be low, but devices will probably work OK.  Or, if not, the breaker/fuse for the outlet will trip.  In that case, you're out of luck.

Just for your information, take a look at the Watts consumed by the hair dryer.  Divide that number by 115 (volts) to figure out how many Amps it requires.

Alex Rutchka, SE #4 '05 MB

PS: See you at Eufaula, AL!
Re: Electrical question
Reply #3 –
Yahoo Message Number: 96626
Jim, as others have pointed out, with that hookup you have a maximum of 1,800 watts to work with, and in all probability it's being shared with other devices in the house, in the coach, or in both.
 One thing in particular to look out for: is your refrigerator set to "AUTO"? If it is, it's drawing 350 watts whenever it's running, which means you're down from 1,800 watts to 1,450 watts. Switch it to "GAS" to eliminate that heavy drain on your reduced electrical resources.
 In addition, your converter is constantly drawing power--I don't know how much the stock units draw, but it could easily be as much as several hundred watts. This too is subtracted from the power available at an outlet.
 In short, you're in straitened circumstances as far as electricity is concerned. Power hogs like your hair dryer and your heat strip are probably not going to be practical to use. If you want to keep warm with electricity, get a small heater that has 750W and 1,500W settings, set it to "LOW" (750W) and leave it there. You can probably get away with that, but anything over 1,000W is probably out of the question while you're running on half power--because that's what you're doing.
 Meanwhile, you have a propane-powered furnace that you can put to good use. :-)

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Electrical question
Reply #4 –
Yahoo Message Number: 96644
Hi Jim,

Others have given you good advice on the limitations of a 15 amp electrical service and I agree.
 I have a Progressive EMS-HW30C in my 2005 MB.  My display panel is easy to see.  Currently I am in a campground connected to a 30 amp service.
EMS says voltage is 126 volts.  Current readings for various conditions are as follows:

- Minimum AC load (converter & microwave control power) -- 3 amps - Add refrigerator (switch from gas to auto) -- 6 amps total - Turn on A/C strip heater (6000 BTU) -- 18 amps total
 (Microwave contains a small power supply that operates the clock and control panel.  It draws a little power whenever the microwave power cord is plugged into a voltage source.)

I assume that the you didn't trip the ciruit breaker that feeds the circuit from which you were getting power and that the Progressive unit shut you down.  The Progressive unit doesn't know anything about the current capacity of the voltage source, so I would suspect that it detected a "low voltage" condition.  You should have gotten an error code of E4.  My unit trips out at about 104 volts.
 If you shutdown due to a low voltage condition, a logical suspect is the cable connecting your LD to the power source.  A common  50-foot long extension cord (16 gauge)will give you a voltage drop of about 6 volts when the current drawn is 15 amps.  If the source voltage is only 110 or 112 volts (typical in many residential situations) the voltage that gets to the LD may be low enough to cause the Progressive unit to shut down.

Doug