Another battery/solar/charging question......

My game plan for my new battery bank of two groups of two 6VDC GC2 batteries in series is to run them down to around 12.0VDC when camping and then use my small 2KW generator to run my converter/charger which is a PD-9260C 60AMP DC Charger. This will get my battery bank past the high current use of around 50AMPS for the first hour of charging per bank when they first get hit with 14.4VDC coming from the converter/charger...

Once I get past the high current ops then my planned three 120WATT Solar Panels will continue to charge the rest of the high sun day getting to at least a 90% charge state before dark hits again...


I suspect I will need to hit each of the two groups with 14.4VDC with around 20AMPS cpacity for the first hour and then the two banks will start tapering back to around 6-8AMPS for a couple of hours and finally down to around 2amps telling me I am at the approcimately 90% charge state.

Just charging using my 2KW Geneartor on my older battery bank would do al lof this in aorund 3 hours or so of generator run time... This was not having solar panels... My converter/charger starts out with 14.4VDC, then after an hour so so it will drop back to 13.6VDC for another remaining two hours it will will run and finally after three hours or so the converter/charger will drop down to 13.2VDC output. This is my so called 90% charge state point. If I continue to run my 2KW generator after this three hour time for another 8 hours or so the batteries would get to their 100% charge state. This is too long a time for camping off-grid hehe... This was my three 12VDC 85AH Interstate batteries in parallel ops I have been doing since 2009 and the three 12V batteries lasted until a couple of seasons ago... 2013 time frame so 4 years is not bad for my use of them camping off grid almost all the time...

My new battery bank will be doubling my capacity (Around 430AHs) and I will be using GC2 batteries which have larger internal cells so this should increase my battery life considerable... On my old battery bank I was drawing a couple of DC Amps 24/7 for parasitic drain and then from 6PM to around 10-11PM I would be draining around 20-25AMPS DC current.

My older battery bank setup made it to 8Am the next morning dropping my 12VDC to around 12.0VDC or so and during breakfast I would start my 2KW generator and start the recharging process for the next three hours...

With adding my solar panels I will only run my 2KW generator for about an hour and then then solar panels will get me back to the 90% charge state before losing high sun hopefully. If that is happening I will run my 2KW generator again for a couple of hours as I learned to never start my evenings battery drains without being at the 90% charge state at least...

My camping off grid battery bank story hehe... I will learn a few different thing I expect charging GC2 6V batteries but hopefully all the charging time will be about the same as using my three 12VDC batteries in parallel... My converter/charger only puts 14.4VDC in the bulk charge mode and the GC2 batteries will want to see 14.8VDC so this will add more time to my scheme I'm sure.




Roy Ken

Probably a WFCO as OEM converter. With 4x T105 I recommend replacement with PD9280-14.8 and pull new #4 wire for the battery charging loop.

http://www.bestconverter.com/9200-148-Deck-Mount

Upgrade the solar to 600 watts and forget about running the genny except for running the air conditioner.

Consider moving to a hybrid inverter/charger. They are not cheap--but they may outperform almost any converter when it comes to recharge rates.

Best of all--just enjoy your RV!

"2 more T105 batts for a total of 4 of the T105."

Your four T105 have a total of 450 12 volt AHs. The general rule is one solar watt per amp hour, so you'll need 450 solar watts minimum. If you have lots of shade or a mountain cuts off some charging time, get 600. As Don said you should be able to forget the generator. Be careful mixing solar panels. Same type and watts is safest.

"Firman P08003 8000 watt generator"

Its not what you can "throw" at your batteries but what will they accept during charging.

jsrore wrote:

We also just bought a a Firman P08003 8000 watt generator.
i had never heard of Firman , did a lot of research and they get great reviews from all over the web.
the reason im asking about the converter/charger is not sure if it has enough power to charge the 4 T105 when i have the generator running...

Now is a good time to replace the converter charger with a combination inverter/charger/transfer switch. These are available from several different manufacturers including Samlex.

Simple installation. Wire your DC distribution panel directly to the battery bank and ignore the converter. Run external "shore power" directly into the inverter/charger/transfer switch. The transfer switch can handle 120VAC @ 30A so you can wire all of your RV AC circuits directly to the inverter/charger/transfer switch.