12v +24v ?

[oldtrack123]

Even a simple switching arrangement that puts the battery bank in series for 12 volt purposes would negate any concerns about uneven discharge states.

Iza

Hi
Do you really mean the above???
AND he is talking about 2x250Amphr batteries!!

What size switch would you suggest, & what switching configuration??


PeterQ

[BruceS]

I took his comment to refer to just having a switch to select battery 1 or 2 but I see you read it properly!
All our suggestions are more like thinking out loud anyway as the price of a converter suggests it's the easy way out.

[oldtrack123]

I took his comment to refer to just having a switch to select battery 1 or 2 but I see you read it properly!
All our suggestions are more like thinking out loud anyway as the price of a converter suggests it's the easy way out.

Hi Admin
You posted while i was typing the below

IF the OP is happy to closely monitor his discharge & charge voltages &
with the light loads [probably less than 10A] he has indicated,
he can use ,A single pole, double throw , centre" off" switch [current rating to suit the max 12V load] Jay car part#ST-0576
Bridge ternminals to make a single pole 20A , Load to centre terminals, batteries POS to each end !!
That is as simple & as cheap as it can be
BUT WATCH those discharge voltages with good meters, one on each battery,reading to TWO decimal places
With his system ,much better to watch the discharge voltages, & keep them even rather than try to balance the charging.

ps I think that as time goes on that 12V load may increase
PeterQ

[TigerMK1]

I will stay simple, the motor requires 24V supplied by the alternator. The house requires 12V & 240V AC . This is supplied by the solar and the inverter feeding a seperate 12V Lithium charging/storage sytem (used to be called a battery) and a inverter that keeps the fridge happy, has enough energy to keep the hot water system hot as well. Now the second alternator on the motor is twiddling its wires, its output is a bit to high for the 12V lithium storage/usage system. I will eventually sort out the second alternator so it can contribute. Meanwhile, my storage sytem (LI) is very happy.

[oldtrack123]

I will stay simple, the motor requires 24V supplied by the alternator. The house requires 12V & 240V AC . This is supplied by the solar and the inverter feeding a seperate 12V Lithium charging/storage sytem (used to be called a battery) and a inverter that keeps the fridge happy, has enough energy to keep the hot water system hot as well. Now the second alternator on the motor is twiddling its wires, its output is a bit to high for the 12V lithium storage/usage system. I will eventually sort out the second alternator so it can contribute. Meanwhile, my storage sytem (LI) is very happy.

Hi

You missed some little but essential details about your setup

What size battery
What size solar charging do you have ?
How long can you last without mains charging??

PeterQ

[TigerMK1]

I will stay simple, the motor requires 24V supplied by the alternator. The house requires 12V & 240V AC . This is supplied by the solar and the inverter feeding a seperate 12V Lithium charging/storage sytem (used to be called a battery) and a inverter that keeps the fridge happy, has enough energy to keep the hot water system hot as well. Now the second alternator on the motor is twiddling its wires, its output is a bit to high for the 12V lithium storage/usage system. I will eventually sort out the second alternator so it can contribute. Meanwhile, my storage sytem (LI) is very happy.

Hi

You missed some little but essential details about your setup

What size battery
What size solar charging do you have ?
How long can you last without mains charging??

PeterQ

I have a 200AH Lithium Pack with 7 solar panels feeding the battery. It runs a F&P 240V fridge 24/7 via a inverter, this also runs the other 240 systems such as satellite TV and microwave when required. If the battery is fullay charged during the day, the 240 element in the gas hot water system is turned on for a short while. If this happens many times during the sunny day, the hot water sytem is fully hot.

With regard to rainy/cloudy weather, 3 to 4 days minimum from the batter, one of the reasons I have so much solar is to cover cloudy/wet days, I can usually get some charge from the panels.

Cheers Steven

[T1 Terry]

with Brian's set up, we fitted a seperate 12v lithium battery and it's charged via a 24v to 12v converter, either switch on when the 24v batteries are full or if the weathers been crook for 4 days straight, a manual over ride will top them back up. This method limits the losses associated with a 24v to 12v converter, it generally only uses solar the batteries can't store and saves boiling the water in the hot water tank, there is only so hot you can handle under the shower, any more is just wasted really.
We intially planned to fit a 12v dedicated panel to keep the battery full but it never eventuated as it wasn't needed, the 12v panel charges the boat/chainsaw/compressor/jumpstart battery instead, those who were at the get together would have seen it in action