A lot old gas barths came with a single output converter. My wiring diagram shows such a converter with a single 6 ga hot out and an 8 ga ground out. The diagram appears to be generic, rather than one drawn just for my year or model.

Anyone can have mine for a donation to the site.

Copy on request.

That's interesting! Makes me more inclined to suspect the converter...

quote:

Originally posted by Tim Grimes:
I also have a brass cutoff throw switch, that was installed to the positive lead of the old house battery. When that switch was closed, the house lights were full bright.

Why would I have any lighting at all (albeit dim) in the coach, with that cutoff switch open? As is (or was, before I changed house battery), before I closed the switch, the house lights were extremely low. I would have expected for there to be no coach lights when the house battery throw switch was open?

Thanks, Tim

Tim, were you plugged to 110 when the above situation occured?

Bill,

I was plugged into 110VAC behind our hangar. I haven't connected the new battery - yet.

quote:

Originally posted by Tim Grimes:
I also have a brass cutoff throw switch, that was installed to the positive lead of the old house battery. When that switch was closed, the house lights were full bright.

Why would I have any lighting at all (albeit dim) in the coach, with that cutoff switch open? As is (or was, before I changed house battery), before I closed the switch, the house lights were extremely low. I would have expected for there to be no coach lights when the house battery throw switch was open?

Thanks, Tim

Tim, were you plugged to 110 when the above situation occured?

quote:

I was plugged into 110VAC behind our hangar. I haven't connected the new battery - yet.

Tim Grimes

OK, now that I understand you were connected to 110, it makes more sense to me.

Assuming the knife switch cuts the positive cable to the coach battery, it could be that the converter is powering your lights when the knife switch is open. But rather poorly. Do this again and unplug the converter. Do the lights go out completely?

There is one other consideration here. Some chargers and power supplies depend on the battery to be in the circuit to absorb ripple and charge to peak. To act as a capacitor, as it were. Since capacitors charge to peak, without the battery, the voltage seen by the load will be .707 of transformer AC peak to peak voltage. This works out to under nine volts, which would translate to dim lights.

So..... you could have a normal situation there. I have not conducted that experiment, but if I can find my old converter tomorrow, I might hook it up and see.

quote:

Originally posted by Tim Grimes:
I also have a brass cutoff throw switch, that was installed to the positive lead of the old house battery. When that switch was closed, the house lights were full bright.

Why would I have any lighting at all (albeit dim) in the coach, with that cutoff switch open? As is (or was, before I changed house battery), before I closed the switch, the house lights were extremely low. I would have expected for there to be no coach lights when the house battery throw switch was open?

Thanks, Tim

Consider that the battery could be wired directly to the coach to supply 12V and the switch actually is switching out the converter. Now, with a bad battery, the lights would be dim because of the low voltage IF the switch is open. Close the switch and now the battery is receiving a charge voltage and the lights would also be receiving the higher voltage.

Could be wired this way because someone mis-connected the two leads, OR it could be intentional as a way to disconnect the charger from the battery. There may be a different switch elsewhere that is meant to disconnect the house from 12V.

Should be easy to figure this out with a simple voltmeter.

quote:

Originally posted by Relative:

quote:

Originally posted by Tim Grimes:
I also have a brass cutoff throw switch, that was installed to the positive lead of the old house battery. When that switch was closed, the house lights were full bright.

Why would I have any lighting at all (albeit dim) in the coach, with that cutoff switch open? As is (or was, before I changed house battery), before I closed the switch, the house lights were extremely low. I would have expected for there to be no coach lights when the house battery throw switch was open?

Thanks, Tim

Consider that the battery could be wired directly to the coach to supply 12V and the switch actually is switching out the converter. Now, with a bad battery, the lights would be dim because of the low voltage IF the switch is open. Close the switch and now the battery is receiving a charge voltage and the lights would also be receiving the higher voltage.

Could be wired this way because someone mis-connected the two leads, OR it could be intentional as a way to disconnect the charger from the battery. There may be a different switch elsewhere that is meant to disconnect the house from 12V.

Should be easy to figure this out with a simple voltmeter.

Mike, Bill,
Thanks immensely for your analysis on this electrical issue. I am inclined to believe this was a matter of a bad battery. I believe that the old house battery was bad, and that condition may have caused dim lights with the open circuit (with the throw switch open); also suspect that the closed throw results in charging the house battery (as you described). I will test properly with a voltmeter once I return to the motor home in a few days. Thanks gentlemen. I really appreciate your assistance.

Well?