Hi.

I'm upgrading from a 5kw Axpert to a 12kw Sunsynk inverter.

I currently have a combination of Pylontech batteries consisting of:

2x UP5000
4x UP3000C

I'm trying to work out how the best way to connect my batteries to the new inverter so any advice would be greatly appreciated.

I am considering the following approach:

- Divide the batteries into two banks. Each bank would consist of 1x UP5000 and 2x UP3000C.
- Connect the positive and negative terminals of each bank to a busbar.
- Utilize one 'master' battery for communication with the inverter.
- Connect the communication cables to all the batteries as per normal

Would splitting the batteries into two banks as described and then joining them at a busbar be a viable approach? Could this effectively enable me to draw the full 12kw from the batteries without exceeding the current rating of the cables? And is it advisable to have only one 'master' battery to manage communication with the inverter?

Thanks

 

53 minutes ago, chmmmr said:

Connect the positive and negative terminals of each bank to a busbar.

Just connect to the DC breaker/disconnect switch  but use the correct rated fuse. See below dgm, in effect its the same as you proposed...You'r just doing it after 3 batteries in each stack.

 

 

Thanks, that is pretty much what i was thinking.  I also assume you can limit the amps the inveter pushed/pulls through the cables?

Chmmmr with those batteries you can pull full power.

4 x Us3000C is 37amp each that is 148 amps in total

Up5000 is 50 amp each that is 100Amps in total

Total available amp is 248Amps. The 12kw max is 240Amp.

I would divide into 2 banks and run double cables from each bank to an busbar. From there to Fuses and inverter.

2 Pylontech cables will not be able to handle the current of the inverter. Please note that all cables should be the same length.

 

Thanks,  i didn't realize that you could do that.  That make perfect sense now.   The Pylontech cables can only carry around 100amps each.  so the busbar and the cable to the inverter should be able to carry 400amps max.

Thanks for your help.

Edited October 31, 20232 yr by chmmmr