Converter question

[Fla2RI]

My converter, located under my bed, runs all the time (fan noise) when I am plugged in and the aux. battery switch is ON. All batteries are new. I found if I shut the aux. battery switch off, the converter fan stops and everything still works. Should I leave the aux. battery switch off when plugged in? Is this normal? Will my aux. batteries charge if the aux. switch is off? Thanks

[W8RLM]

I'd get the batteries checked to see if you don't have a bad cell. That would cause the voltage to drop, and he converter would sense that and would turn on.

If you turn off the auxilliary batteries, you could find out if there is a bad cell by watching the battery voltage. If it continues to drop, then you either have a phantom load that is connected ahead of the auxilliary switch, or a bad battery.

Depending on how your coach is wired, running the 12 volt circuits on the converter shouldn't be a problem. If the AC voltage surges, you may get a higher DC output. With the bateries on, they tend to help as a voltage regulator.

W8RLM - Bob

[DandS]

As Bob stated, if your converter is running constantly, that would indicate a problem with your batteries. You can turn the switch off but then your batteries will not receive a charge and eventually will run down. Best to identify and fix the problem.

[Fla2RI]

I'll check the batteries, I figured the were ok because they were brand new in March. Thank you.

[hamguy]

Quote:

Originally Posted by DandS As Bob stated, if your converter is running constantly, that would indicate a problem with your batteries. You can turn the switch off but then your batteries will not receive a charge and eventually will run down. Best to identify and fix the problem.

In my experiences all converters run constantly. Most converters are either fixed voltage (very poor) or 3-stage. The fixed voltage are set at some voltage, around 13.8, and are constantly pumping that voltage and the associated current at the batteries. This will cause the water to boil off in a very short time. Keep a cautious eye on battery status if you have this type of charger.

A 3-stage also runs all the time but senses the battery condition. It will start at about 14.2 volts to bring the battery up to near full charge, Then it will drop the forcing voltage down to about 1.8 to complete the charge. After that, is will drop the voltage to 13.2 to put a trickle charge into the batteries.

A voltage of 14.2 will boil a battery dry rather quickly. A 13.8 volt charge will still cause water to boil of albeit slower. A charge at 13.2 will maintain the proper charge voltage of ~12.6 V without dropping water appreciably.

[DandS]

The OP was referring to converter fan noise which was constant. Agree most converters run constantly but the fan shouldn't. If it does, it could indicate the converter is overworking due to a bad battery. Sorry - should have said "converter fan".

[wa8yxm]

Actually.. There might well be nothing wrong with the batteries, or anything else, save for State of charge...

Hook a digital voltmeter to the batteries, DIRECT to the batteries and note the voltage, for posting here

Then turn on the disconnect switch (Re-connect) and again note the voltage for posting here

Wait 4 hours,, Note the voltage a 3rd time and post here.

Oh, and that 4 hours .. Don't watch the clock, if it's 3 hours or 6 hours, or whatever hours, the idea is "Hours"