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Author Topic: Automatic Transfer Switch Conundrum  (Read 349 times)


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Automatic Transfer Switch Conundrum
« on: August 30, 2017, 06:53:38 AM »
After an eight hour drive in my 2005 Horizon 36RD, I plug into shore power and no AC outlets in the coach are hot. The only AC related device that works is the hot water heater. The inverter remote is displaying "dead battery" and when I disconnect shore power the display is dead and refuses to even back light when I push the power on/off button. I called the W hotline and the technician thinks I have a bad automatic transfer switch. The switch that I receive is not an exact match but I get it installed and voila! Nothing changed. In probing around I find that the leads going to the inverter are dead. This leads me to the battery compartment and there I find the positive wire disconnected from the grommet. Now everything is back to normal. My question is why would a disconnected wire at the battery cause all my AC outlets to fail?
2005 Itasca Horizon 36RD


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Re: Automatic Transfer Switch Conundrum
« Reply #1 on: August 30, 2017, 07:06:17 AM »
The AC for the coach goes through the inverter except for the hot water heater, air conditioner and maybe some other high current devices.  When the 12v wire was disconnected the inverter was did not have current to cause its "internal transfer switch" to function.  Thus you didn't have AC on the leads that the inverter switches.  The hot water tank was working and probably your air conditioners would have also worked as well as the engine heater.

Bill Bell -- SW Florida
Sailboat -> Powerboat -> Motorhome -> Rest Home -> Funeral Home
Presently between Motorhome and Rest Home

John Canfield

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Re: Automatic Transfer Switch Conundrum
« Reply #2 on: August 30, 2017, 07:52:42 AM »
^^ What Bill said ^^
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