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Topic: The solar controller display question  (Read 321 times) previous topic - next topic
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The solar controller display question
Until I get a battery monitor this is all I have.

Does the voltage readout show the volts the converter is charging at or just the panels?

I noticed when I unplug from AC the voltage drops so I was wondering if the DC voltage showing is what the converter is charging at.

2021 Mid Bath
Re: The solar controller display question
Reply #1 –
Hi Ted. That display is the voltage that the batteries are at. The SB3000i throttles back the solar to 'float' because your Parallax is charging the batteries.  When you unplug, the converter charger goes away, so the voltage drops. If you have sunlight, and the batteries voltage 'droops' enough, the solar boost will switch back to 'absorption' mode.  If the batteries are pretty much charged, the SB will stay in 'float'.  If you start the engine, the alternator isn't a multistage charger and the battery voltages should go up to what I consider to be a high voltage. 13.5 to 14.8 or so.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: The solar controller display question
Reply #2 –
Also, as you scroll through the display readings, you’ll come to the Aux Volt reading.   That is your engine battery reading.
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: The solar controller display question
Reply #3 –
Quote from: RonB  - 
Hi Ted. That display is the voltage that the batteries are at. The SB3000i throttles back the solar to 'float' because your Parallax is charging the batteries.  When you unplug, the converter charger goes away, so the voltage drops. If you have sunlight, and the batteries voltage 'droops' enough, the solar boost will switch back to 'absorption' mode.  If the batteries are pretty much charged, the SB will stay in 'float'.  If you start the engine, the alternator isn't a multistage charger and the battery voltages should go up to what I consider to be a high voltage. 13.5 to 14.8 or so.   RonB

I have the 2 - 115W solar panel option and I'm in the learning phase about my system.

Will the Parallax 8355 with its 3 stage charger and TempAssure sensor keep the AGM batteries topped off properly when plugged in to shore power?

Most of the time at home I will use the panels to keep them topped off.

I heard that AGM batteries need a higher charge voltage than my previous Trojan T-105's.

I just don't want to damage them.
2021 Mid Bath
Re: The solar controller display question
Reply #4 –
Hi Ted; if anything the AGM batteries may need a slightly lower voltage. Because they can't vent, and water can't be added, they are considered to be more 'delicate' to overcharging.  Your motorhome is properly set up for AGM. I think the solar, 230 watts, will keep the batteries properly charged.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
 
Re: The solar controller display question
Reply #5 –
No need to guess. See page 19 of the Lifeline Technical Manual for charging recommendations for those AGMs.
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: The solar controller display question
Reply #6 –
Quote from: Andy Baird  - 
No need to guess. See page 19 of the Lifeline Technical Manual for charging recommendations for those AGMs.

Thanks.
I hope the new ones will be okay.
There is an elaborate installation/charging process I won't be able to perform.

I had zero issues with my Trojan T-105+ batteries. I will seriously consider going back if these don't work properly.
2021 Mid Bath