12v question

You don’t use a transformer to reduce DC voltage. Transformers require AC. You would have to use a power converter which is an expensive “fix” for low voltage alarms. Check engine charging and replace 12 volt house battery would be my recommendation (fixed mine).

If you do go the power converter route it should be fine for 12 volt house load. Grounds would be connected together. When you say the "batteries are parallel" which is what I would expect then you say "I'll connect B to a 36v to 12v /20a stepdown". With parallel batteries it wouldn't matter which battery positive you connect to.

If you are using heavy duty dredge reels like 12 volt LP's a power converter is not recommended.

Are you saying you have one 36V/60Ah battery or you have three 12vdc batteries in series to power your TM.?

If you have three 12v batteries powering your TM then you can, in some ways, rig it to also use them in parallel as 12v house.
One upside to using three 12v is simplifying using them as House.
The big upside is being able to charge them from motors.


You can't connect 36V to 12 V House. You will get a 36v House and break stuff. You can't step down using a transformer. Transformers work on AC not DC.

You would need a 12VDC regulated power supplyy that is fed by 36Vdc (38.4Vdc). I'm sure they make such a thing. Maybe that is what you are refering to when you say 36v to 12v step down. But its not a "transformer".

I just installed a TM and went with a single 36V vs three 12v. I can only charge from an AC powered 36vdc charger.
Not planning to look at using it for 12v house since I would not be able to charge House from motors. (again, there's probably a 12V to 36V charger out there...)