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Topic: Trouble shooting factory installed solar (Read 645 times) previous topic - next topic
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Re: Trouble shooting factory installed solar
Reply #25 –
It doesn't appear the SB3000i has a battery sensor,
the SB3000i Temp sensor does.
2002 30' IB
Re: Trouble shooting factory installed solar
Reply #26 –
You would use a pair of 100 A-hr lithiums wired in parallel instead of a pair of 225 A-hr 6V batteries wired in series. The lithium batteries do not need a temp monitoring function - it should be disabled.

Steve
2004 FL
2013 Honda Fit
Re: Trouble shooting factory installed solar
Reply #27 –
Mark.  The SB3000i is the same in both. The one that is $30 more comes with a $30 temperature sensor, for installation with lead acid batteries that generally need a compensated charging voltage, dependent on the battery temperatures.   The Lithium batteries are generally only available in 12volt (really 12.8 volts ranging up to 13.3 volts at full charge) or 24 volts; that won't work with a 12 volt designed motorhome.
   You can go with a single 12 volt Lithium battery.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Trouble shooting factory installed solar
Reply #28 –
"You can go with a single 12 volt Lithium battery."
That's certainly cheaper than two lithium batteries. Could you suggest one?
2002 30' IB
Re: Trouble shooting factory installed solar
Reply #29 –
Wouldn’t Mark also need a lithium compatible converter?
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Trouble shooting factory installed solar
Reply #30 –

Hi Greg;  The advantage here is that Lithium batteries don't require as high a voltage to charge as lead acid batteries do. So the factory supplied converter, that outputs 13 to 14 volts to charge a lead acid at a higher rate, will do fine with LiF. It won't charge as fast as the LiF can accept, and the four stage converter feature is wasted because the bulk/absorb/float/equalize actually gets in the way of quick charging a LiF battery.
    My 1999 came with a Magnetek 6345, and it had two outputs and a relay that disconnects the battery, uses a more regulated output to run the house 12v circuits, and a less regulated circuit to charge the battery. (not well, not fast).
    Reprogramming the SB3000i Solar controller essentially removes that feature from the solar PV output.  
    Similarly, I believe that in 2002 the factory was still using diode isolator separation, so the voltage applied to the battery from the engine alternator should be up at 14.8 volts. My installed Multiscan showed that voltage for about 20+ years while I drove.  That will charge a LiFePO4 battery well. The built-in BMS will protect the LiF battery from overcharging.
    Less expensive Li batteries are out there, but my recommendation as (always) is the SOK 206. Metal case, built in heater, Bluetooth with capacity SOC, and a good track record. Two hundred amp hours for $585. And UL approved also.
  Amazon.com: SOK 12V 206AH Lifepo4 Lithium Battery, 4000~8000 cycles Support...
   Bottom of the barrel choices abound. I wouldn't go cheaper than: Amazon.com: ADCBATT LiFePO4 Battery 100AH, 12V Lithium Battery with Low Temp...  You aren't doing yourself or any 'next owner' of your rig a favor with the 'low price leaders' out there.  Some of the batteries that Will Prowse has torn apart in the past are examples of 'a dangerous waste of money' items.    RonB
 

As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Trouble shooting factory installed solar
Reply #31 –
"That's certainly cheaper than two lithium batteries."

It's not a case of one battery being cheaper than two. Your current pair of batteries give you 225 amp hours at 12 V, and I assume you don't want less than that. So if you go lithium, you want about 200 Ah, whether it's in the form of two 100 Ah batteries or a single larger 200 Ah battery as Ron suggested. (Lithium batteries deliver more power than similarly rated lead-acid batteries, so 200 Ah of lithium are comparable to 225 Ah of lead-acid.)

So lithium isn't a cheap solution. But it can be cost-competitive with lead-acid, and it offers several advantages. And it certainly won't hurt the resale value of your rig.
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: Trouble shooting factory installed solar
Reply #32 –
Thanks!
For now I hope I can recharge my current batteries enough start the generator. I need to cycle Start-Bil through the system before I store is for the Winter. In the Spring I'll replace the acid batteries with a lithium battery.
2002 30' IB
Re: Trouble shooting factory installed solar
Reply #33 –
Hi Mark; You can also start the vehicle engine and have it running. The alternator can feed power directly to the house batteries on the order of 100 Amps or so. This will assist the house batteries. They could be nearly dead, if you ever really needed the generator to start and run. The generator provides 110VAC power back to the converter. The converter then provides 14.5 Volts DC back to charge the house batteries.
   Three sources can simultaneously charge the house batteries.  1) Solar power from sunlight on panels, via the solar controller.  2) V10 engine Alternator if it is running and has spare power. The engine comes first, headlights/other lights, A/C clutch and fans, dash and radio, chassis battery, engine computer.  3) Converter power, using 110vac from the generator converted to 14+volts to charge the house batteries. And of course if you have shore power 110VAC, that will provide 14vdc to the house batteries to help start the generator.
     Some gensets also provide a small 12vdc output from the genset back through the 12volt starter line, but I think that is for residential emergency generators where the battery is only used to start the generator, after a power failure.  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
 
Re: Trouble shooting factory installed solar
Reply #34 –
Thanks Ron. Great information.
As soon as my current batteries are fully charged, I'll attempt to start the generator.

Happy Holidays!
2002 30' IB