HarryN
Solar Addict
I am in no rush. I know I cant just drop in my batteries. I need to at minimum disable my automerge and add the DC to DC charger. If I dont the batteries have the ability to pull 100% of its capacity for hours on end. Adding the bus bars and fusing to them will be helpful if I add anything in the future.
Am I thinking correctly that I could simply just install the batteries and new DC to DC charger and simply use all the current wiring and just run the current wiring from the RV systems already installed to the positive and negative terminals skipping adding the bus bars. Then I only need to be concerned with the parallel wiring connecting the two new batteries. Since they have a BMS rated for 300A I only need 2/0 for this short of a length. In my original layout I was going to use the 4/0 to the bus bars so I knew I would have extra to sue to connect the batteries in parallel. Should I worry about a fuse between the two batteries? Do I rate that fuse at 125% of the BMS then?
With Li batteries and a built in BMS, I would still put a breaker in between each battery and the bus bar.
There are a couple of reasons.
- If / when the BMS trips, the way that they are re-set is to disconnect it from all other sources of power. Flipping a breaker on / off is so much easier than getting out the tools.
It also is not so easy to tell if they have tripped, so sometimes flipping them on / off can just be reassurance that it is not tripped. This also can replace the need for a fuse in that location.
- When you have a battery based power system with this much "umph", you will want an easy way to turn power off for different sections to work on it and do minor edits.