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Drawing 10 -12 Amps from batts w/ gen on

March 27, 2020, 09:20:12 pm

Good evening everyone,
I'm running my generator and I am still drawing 10 amps from my batteries which are fully charged.
My inverter is on standby and my charger is charging.
Turned the gen off and the inverter turned on and the charger went to standby.
Any suggestions?

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Re: Drawing 10 -12 Amps from batts w/ gen on

Reply #1 – March 27, 2020, 10:44:31 pm

I am not sure that I know the answer, but my meters show similar draws.

I always assumed that it was the 12 volt system drawing amps.  Things like the 12 volt lights

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Re: Drawing 10 -12 Amps from batts w/ gen on

Reply #2 – March 28, 2020, 04:28:24 am

Thanks,
Well it's 3:30 in the morning and I'm using a half an amp and my charger has gone to the ready light.
Still don't know what was using 10 amps earlier..

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Re: Drawing 10 -12 Amps from batts w/ gen on

Reply #3 – March 28, 2020, 06:19:17 am

Frank,

If this is only happening when the generator is running, your generator don't have an alternator so the fuel pump, fuel shut off solenoid, and control circuit have to get there power from the 12 VDC buss. Our generator draws about 8 or 9. Now if you are running the generator and you are down to 1/2 of an amp I have no clue.

 Mike

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Re: Drawing 10 -12 Amps from batts w/ gen on

Reply #4 – March 28, 2020, 08:39:23 am

The picture of the Victron BMV show 12.8 amps (positive number).  I think that is charging amps going into the battery.  So your inverter/charger is drawing 20 amps (approximately: over 10 and less than 20, second picture) of 120 VAC to put 12.8 amps of 13.73 VDC to charge your batteries.  Sounds like it's working ok.  Unless you're asking what is causing your battery to need 12.8 amps of charge?  Inverter/charger could be finishing an absorb charge.
Various things could be using battery power.  Do you have an echo or trickle charger to keep your chassis batteries up?
Is inverter on standby?  Any 12 volt lights on?  Dometic fridge uses some 12 VDC even when on 120 VAC.

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Re: Drawing 10 -12 Amps from batts w/ gen on

Reply #5 – March 28, 2020, 12:33:49 pm

Some have a dual powered instant hot device that in our coach has an unlabeled 12v power switch on the front of my kitchen counter.  If left on the draw is similar to your measurements?

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Re: Drawing 10 -12 Amps from batts w/ gen on

Reply #6 – March 28, 2020, 06:54:55 pm

Thanks all,
I had ran the batteries down to 70% earlier in the day and I think they were just being charged.
What through me is that they were at 100 % and still showed a draw.

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Re: Drawing 10 -12 Amps from batts w/ gen on

Reply #7 – March 28, 2020, 08:44:59 pm

Try shutting off the salesman switch.  That shuts off most (but not all) 12 volt loads.  See what the BMV says.  Your Prosine takes a considerable amount of power just to be on.  Shut it off as well.  See what the BMV says.  Keep looking.

"When you eliminate the impossible, whatever remains, however improbable, must be the truth,"

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