Converter Question

[henw]

I managed to kill my batteries.

They drained to 7V without my realizing what was going on.
So, I have new batteries with clean connections now, but, the Ultra III 55 amp three phase converter (from Best Converter) doesn't charge them.

I measured the voltage being delivered to fuse plate of the converter at 12.08V when plugged to shore power. 30 amp voltage is good.

Everything electrical works on batteries, or when plugged in.

Does that reading imply a bad converter?
Other thoughts?

Tom W

[pgr32e]

Initial charge voltage should be about fourteen and a half volts or so and if it's a three stage charger then as the charge level goes up, the voltage is stepped down.. Sounds like the converter isn't doing what it's supposed to.

[HowieE]

Try this. Turn some lights on in the trailer and determine their brightness. Now have someone disconnect or turn off the convertor. If the lights dim the convertor was charging the system.

I say this because I am not sure where you measured the 12 volts, sounds low for charged batteries or if the meeter was accurate.

The light test will give you a good indicator.

[henw]

I measured the voltage at the positive and negative feeds to the fuse board.
If I disconnect the converter I suspect the lights would not run as all the dc power seems to run through the fuse board.
Where the dc lines enter the AS, there is a relay switch with two fuses sitting on top of it. Could that be involved?

Also, fan on converter only runs when I first turn on the power to the AS. Makes me thing further that converter is malfunctioning.


Tom

[henw]

Well, now I just don't know. Power to fuse board seems to be just what the battery charge is. Whether plugged in or not. I would appear this is not the place to measure charger output.
Is there another way to test voltage output from converter to batteries?

[HowieE]

You can measure voltage directly at the battery with the convertor on and then with it off. If the voltage drops when the convertor is disconnected it was working.

When I suggested disconnecting the convertor for the light test all you have to do is either pull the convertor AC plug if you can get to it, disconnect the shore power, or turn off the AC fuse that supplies the convertor.

As for the convertor fan it will cycle against a thermostat while the convertor is charging to reduce the heat of the convertor. If it is working correctly it will cycle often if you have all the 12 volts lights as that will put the max load on the battery and call for a full charge.