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DC Electrical Question

October 31, 2020, 09:54:10 am

After installing new 8D agm house batteries, and with monitoring the Heart Interface digital readout for the volts when in Charge mode-float, the voltage drifts between 13.25 and 13.55.  Now, with this variation, the AH motor rpm also varies and follows along  with the voltage drift.  If I take the batteries off of charge, the voltage goes to 12.7 or so.  No drifting of the voltage, and AH motor maintains a constant speed.  No other DC applications seem to be affected, I.e. no flickering lights.  Heart Interface 25 inverter/converter.  Shore line hookup.
Is there something going on that should concern me?
Thanks, Mike

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Re: DC Electrical Question

Reply #1 – October 31, 2020, 10:22:06 am

Mike which specific aqua hot motor are you talking about? Are you talking about us a blower inside the coach or pump in the unit itself? Personally I've not noticed any variations in my aqua hot voltage wise but I do use lithium batteries and they tend to maintain their voltage pretty well.

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Re: DC Electrical Question

Reply #2 – October 31, 2020, 10:27:52 am

All the charger inverters I have had do not go up and down on the float voltage. I can hear the pump motor change rpm's when I hook up shore power after letting the inverter run for a few hours, but on float it stays steady.

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Re: DC Electrical Question

Reply #3 – October 31, 2020, 10:28:58 am

If you have the optional remote temperature sensor, unplug it at the inverter/charger and see if that makes a difference.

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Re: DC Electrical Question

Reply #4 – October 31, 2020, 10:39:47 am

Remote temp sensor for what?
Mike

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Re: DC Electrical Question

Reply #5 – October 31, 2020, 10:58:25 am

Think he means the battery temp sensor connected to the house battery.

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Re: DC Electrical Question

Reply #6 – October 31, 2020, 11:11:56 am

Ok.  With 'Remote' unplugged, on the Heart Interface Link2000 panel, voltage reads constant 13.40, 'Charge' light is on but no 'Charge, Accept, or Float' indication on bottom of panel.  With 'Charge' deselected, voltage remains constant at 13.40, so I am assuming with Charge deselected, it is really not deselected, and voltage is coming from converter, not house batteries.  With the constant voltage, AH motor was running with a constant speed.
Mike

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Re: DC Electrical Question

Reply #7 – October 31, 2020, 11:36:10 am

With temperature sensor disconnected, be sure you have entered/programmed your inverter/charger (battery technology, battery bank size and ambient temperature)!

May take more than a few minutes for even a perfectly operating inverter/charger to go through all three stages.

Might unplug from shore power (with remote battery temp sensor unplugged), plug back in and watch voltage for half a day.

Should go through BULK, ABSORPTION and then FLOAT.

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Re: DC Electrical Question

Reply #8 – October 31, 2020, 11:47:03 am

By chance is the switch on the inverter itself in the off position? IIIRC it need to be in the off position for the link to control the inver: charger.

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Re: DC Electrical Question

Reply #9 – October 31, 2020, 12:03:27 pm

The Remote plug that is on my unit is the Remote Jack, which I think controls the Link 2000 control panel in the coach.  That is why when it was disconnected I could not control the Charge or disconnect from converter, I think.  Don't see any plug for a 'Remote Temp Sensor'.
Mike

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Re: DC Electrical Question

Reply #10 – October 31, 2020, 12:10:34 pm

The toggle switch on the Heart was in the on position.  I put it in the off position, and didn't see any difference with indications on Link2000 panel.
Mike

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