Sportster
New Member
If I run two 12V batteries in series to supply 24V to a 24V inverter, can I run a small 12V rv system (mostly LED lights) tapped off one of the two batteries that is wired in series to get 12Vs??
Thanks
Thanks
Can you run 12V system from 24V battery pack
- Thread starter Sportster
- Start date
MisterSandals
Participation Medalist
No, your batteries will quickly become unbalanced and become a charging nightmare.
You should get an 24V to 12V converter. Do yourself a favor and get one that is plenty big or multiple to run in parallel.
Many offerings like this:
Ampster
Renewable Energy Hobbyist
You can, but as others have said, you will unbalance the two parts of your pack. As suggested, a converter is a better way to get 12 volts out of a 24 volt pack. Size the converter to run your LEDs, which typically do not draw much current.
Sportster
New Member
Thank You
Sounds like simplest is to just use a 12V inverter so I can use lights without having to power-up the inverter.
Sounds like simplest is to just use a 12V inverter so I can use lights without having to power-up the inverter.
chrisski
Solar Boondocker
- Joined
- Aug 14, 2020
- Messages
- 5,234
Depends on the size of the inverter and usage. On 12 volt inverter, I warmed meals up on a microwave for two minutes five or six times a day, but not cook for 20 minutes pulling about 2000 watts and 175 amps from the battery. At 24 volt inverter, I run close to 2000 watts at 75 amps for hours on end.
I like 24 volts much better, and my RV DC electronics is run off 12 volts. This 12 volts comes from the as mentioned 24 volt to 12 volt step down converter.
Sportster
New Member
No, a existing rv. Just want to be able to run 12v lights from factory system without powering up inverter.
Rednecktek
Solar Wizard
I just grabbed a beefy Uxcell 60a converter for my project.
MisterSandals
Participation Medalist
Did you purposely get a non-isolated converter?
Third Rail
New Member
- Joined
- Aug 16, 2020
- Messages
- 4
If you take 12V from each battery to a common12V bussbar, then from the bussbar to a 12V fuse block, how is the 24V pack unbalanced if the 12V load is being shared? If it is for minor amperage consumption, that is what I would do.
Rednecktek
Solar Wizard
I got that one because I needed upwards of 40a of 12v supply if all my heaters tried to start at once, so 60a seemed like a safe overhead for the price. There were fancier ones but I was on a pretty tight budget.
Why does my gut tell me that would be a short on the 24v end?
Bud Martin
Solar Wizard
- Joined
- Aug 27, 2020
- Messages
- 4,844
The OP setup has two 12V in series to make 24V, so if you join the 12V terminal of each battery at the buss bar, you will short out the battery.
If you draw up the diagram you will see why it will not work.
Ampster
Renewable Energy Hobbyist
As mentioned earlier, you would have to disconnect the series connection between the two batteries, one would be positive and the other negative. Otherwise when paralleling them they would short. That is a lot of work and there is no way to run the lights at the same time as the inverter.
Last edited:
Assuming this is enough power for your 12V system this would work: https://www.amazon.com/Victron-Energy-Orion-Tr-240-Watt-Converter/dp/B01LZZAXA9
Rednecktek
Solar Wizard
9a for almost $70?? Ouch!
Sportster
New Member
Took a minute for me to picture diagram, but I see what your saying.
Zwy
Emperor Of Solar
This is what I use for all the 12V items in my truck camper. https://www.amazon.com/gp/product/B07QXV8V2L/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1
The price has increased for that particular converter but I see other sellers with the same converter for the less. I wanted about a 30A output and I derate most Chinese electronics 50%. This is why I use a 60A model. Unit has been flawless for coming on 3 years now, holds a steady 12.5V output and I never turn it off as the standby draw is almost non existent.
I see in another reply you were thinking of abandoning a 24V system and instead reverting back to 12V. Once you start using a 24V system with higher wattage items such as microwaves, blow driers and even a refrigerator (yes, most 12V compressor fridges run on 24V) you wonder why you would consider a 12V system. I don't have to worry about excessive heat generated in connections, wire and the inverter.
LeoThomson
Solar Addict
- Joined
- Jun 20, 2022
- Messages
- 3,469
In addition to the other suggestion, you can wire 2, 12V lights in series, add a small converter for each light after the light switch, or add a separate small 12V battery that you charge from the 24V battery. Just to give you some ideas.
Sportster
New Member
My fridge is either propane or 110V., no 12V. It runs quite efficiently on propane but occasionally it will blow out when travelling, figured a switch to 110V while travelling would solve that issue.
Sportster
New Member
I am not going to add anything to an otherwise very good working 1 yr old trailer.
The biggest draw would be 12V water pump for showers, which we have managed quite well in the past for 2-4 days at a time on a single lead/acid battery before even thinking about a charge.
A simple 12V inverter to provide 110V for occasional microwave warming &TV is all that we require.
