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Electrical systems, 1993 U300

March 28, 2013, 08:10:43 am

Under the foot of my bed, with the bed up, are several items
1. the Progressive EMS50C surge protector
2. The auto transfer switch
and
3. labeled "Dual Manual transfer switch.

I know and understand the function of #1 and #2.
But what is the function of #3 "Dual Manual Transfer Switch"

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Re: Electrical systems, 1993 U300

Reply #1 – March 28, 2013, 08:22:29 am

I was curious and did a quick search on web and found this,
Dual Motor Automatic Transfer Switch



Bulletin: #07120
Description
The Lake Shore Electric Corporation Dual Motor Automatic Transfer Switch provides dependable, positive, programmed delay transfer to an emergency power source in the event of normal power source failure. The switch returns the system to the normal power source in an orderly fashion when normal power is restored. In the event that the emergency source fails, the switch will automatically return to the normal source when it becomes available, bypassing all time delays.

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Re: Electrical systems, 1993 U300

Reply #2 – March 28, 2013, 11:34:51 am

Bill, Isthere a wiring diagram in the Foretravel Owners Manual that shows that setup, would be interesting indeed.  Sorta has the SNAFU sound.
Dave M

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Re: Electrical systems, 1993 U300

Reply #3 – March 28, 2013, 11:57:05 am

Bill,
I believe that is part of your OEM inverter (likely a Traytonic) setup.  The older inverters didn't have an internal transfer switch so Foretravel had to add their own and located it under the bed.  Here's a recent post on the subject: Problem with GFI circuit
My coach actually had two of these boxes since the inverter had a master switch for selecting "outlets" or "microwave" on the inverter control panel.
I now have an updated inverter (internal transfer switch) and still use one of these boxes to switch the "outlets" power when I'm camped at a place that only has 30 amps and there's an available 15 amp outlet that I can plug into also.

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Re: Electrical systems, 1993 U300

Reply #4 – March 28, 2013, 04:20:16 pm

John:

I also have a 1991 U300 with the original 1500 watt inverter, so I'm thinking I must have one of these switches and I was not aware of it. I also have the switch to choose between outlets or microwave. I used our coach for several trips last year both boondocking and with hookups and didn't notice any issues. When does one need to use the manual transfer switch? I read the linked post above, and I think it answered my question. The relays are activated when the inverter is turned on. I will check this out on my coach as SOON as I can get it out of storage...

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