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Autoformer transformer by AEI

December 30, 2010, 11:31:50 am

We bought this 96 U320 seven months ago trying to get to know, and understand everything.  Under one of the bays I found a grey heavy box with a 50 amp cord and a 50 amp receptacle, It says Autoformer on it. I can't ask the old owner because he passed away, Called company about unit and they were newer owners so they didn't have any knowledge of the older units.It says it is a RV 220-50A or TL is has a date on it  8-2-2000. It has one toggle 3 way switch on it that says up is manual mode, down is automatic, and maybe center is off. Plugged it in and the volts went to 130 I don't know if that is OK.  If anyone has knowledge of this device I would appreciate it.      Thanks  Art

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Re: Autoformer transformer by AEI

Reply #1 – December 30, 2010, 11:38:31 am

I would test it with a voltmeter (not the coach) while plugged in and try the three switch positions.  RV Autoformers are designed to boost the voltage received at a campground when it is too low to be safe.  I suspect it was in the manual boost mode when you tried it (assuming the input voltage was normal).  Try moving the switch and see what happens.

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Re: Autoformer transformer by AEI

Reply #2 – December 30, 2010, 12:59:17 pm

I have used the Hughes Autoformer units (installed in my storage bay) in my 1998, 2002 and 2009 Phenix Foretravels and would not be without a voltage booster. I had a unit such as you described and I liked the switch but they have eliminated it since the current units are all automatic and therefore they do not have the manual bypass capability with the switch in the "OFF" (middle) position. Your unit will boost the voltage 10% if the shorepower voltage coming into the Hughes Autoformer is below 117 volts. If the incoming voltage is 117 volts or above, the unit is supposed to just pass thru the voltage. Therefore, your switch should do the following:
"UP" Position (Manual Mode) = Voltage will "Always" boost 10% regardless of the incoming voltage.
"Middle" Position (OFF) = Voltage will just pass thru without any boosting.
"Down" Position (Automatic) = Voltage will boost 10% if the shorepower voltage coming into the Hughes Autoformer is below 117 volts. When the incoming shorepower voltage goes to 117 volts or above, the Hughes Autoformer will not boost and just pass thru the incoming voltage.
I hope this helps you to understand the workings of your Hughes Autoformer. If you have any other questions/concerns you can email me at edschwaco@yahoo.com or call me at (254) 744-6227.

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