EMS error code E-2: ground fault

[Jimsue]

My fifth wheel is hooked up in my driveway to an 110 outlet in my garage via a 50 amp cable stepped down to a 30 amp extension via a dogleg then to the 110 wall socket via a three pronged adaptor . Not running anything that draws a lot of amps, just basically charging 12v battery, playing the radio. Today, I thought I'd try the electric water heater and everything shut down. My HWC 50 amp EMS read out an E-2 error message and a subsequent call to progressive industries tech support ( very good support, BTW) had me checking the 110 wall outlet in the garage with my multi meter, where it was revealed that a ground fault was present on that circuit. Plugging in to a different outlet in the house put me back to normal power in the fiver and The error code disappeared.
My question is: If my electrical ran fine all week plugged in to the garage outlet, why did it all of a sudden give me the error code for a ground fault? Can a ground fault appear randomly or be "caused" by too high a demand for voltage by something like turning on the electric hot water heater ? I realize that I was cutting it close by stepping down my 50 amp system to 110, but I was not running the AC , microwave or power tools. .. And why did it suddenly recognize a Ground fault on a circuit that checked out fine initially ? I'm glad my hard-wired EMS picked up the error (thank you, Turbs) but am curious as to whether or not a ground fault can be caused by pilot error, so to,speak...thanks for any light you can shed on the subject


Jim.couillard at gmail
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