Re: Autoformer
Charlie, that's a tough lesson to learn, but don't blame Hughes for it. Its the chance you take when you buy off of Ebay.
There probably should only be one light on when the unit is operating. It logically would be the RED light. The AMBER lights (on yours) probably came on when the unit was BOOSTING. The fact that your AMBER lights are on all the time could mean that your's is boosting all the time, and that probably indicates a faulty unit. You could check the output with a voltmeter to confirm whether it is boosting or not.
My logical assumption could be completely upside down. It could be that the AMBER lights go OUT when it is boosting.
ARCHER, an autoformer is a transformer with extra "taps" that get switched into the output when the park line voltage gets below 112 volts (usually). It "boosts" the line voltage back to 117 when that happens to keep the MH at 117 volts. When the park voltage is "OK", it just passes it straight through.
LOOK OUT FOR TECHNICAL STUFF: The term autotransformer usually designates a particular type of transformer; one that has a common connection from the input to the output. This configuration allows them to make a smaller transformer for the same current handling capability. This also means that this transformer configuration does not isolate the output from the input.
I notice now that Hughes is selling a larger and more expensive tranformer. It probably is a different configuration that isolates the output from the input. I'm guessing, but if that is the case, then it won't be called and autotransformer.