Hello Power People, 

I'm posting this here to hopefully save anyone in a similar situation a lot of headache and possibly an inverter. 

I recently installed a Growatt SPF5000TL inverter and a Pylontech US3000C battery. From what I could research on this forum, firmware updates were required to get the BMS communications established. So, I got the firmware and commenced the updates. It broke my inverter! It would not turn on after the 2nd update. Luckily it was still under a warranty and the supplier swapped out the unit. 

I was really not comfortable with doing a firmware update on the new inverter, so I found some more information with regards to the cable and managed to get the BMS communicating WITHOUT DOING ANY FIRMWARE UPDATES. So, if you would like to get the inverter and battery communication, follow these  steps.

1. If you are unable to make your own CAT6 network cable, go to your local computer shop and ask them to make one up for you. 

2. The cable only requires 3 wired contactors. Refer to picture below:

3. Invert the the wires on either end of the cable connections. It doesn't matter what the colours are, as long as they are inverted in order and pin location.  

4. Turn the battery off. and set your Baud rate to 9600. Dipswitches 1 0 0 0 (1-ON 2-OFF 3-OFF 4-OFF)

5. Connect the end with contactors 6, 7 & 8 wired to the battery RJ45 port. Then connect the end with contactors 1, 2 & 3 wired into the BMS port of the inverter. 

6. Turn the battery on and inverter back on. 

7. Go to setting 5 and select Li with protocol 04. Make sure it is set, then press escape and it should start communicating after a few seconds.

8. If it doesn't work immediately, turn the battery off on the red SW switch and then the main switch then turn the inverter off. Wait 30s and turn back on starting at the battery. 

9. To verify that it is communicating, got to setting 12, 13 & 21. These will now be displayed as percentages and no longer voltage. You will also see a Li display next to the battery on permanently. 

 

I really hope this is able to help someone out there. If you have any questions, please don't hesitate to ask. 

Neil

  

I tried your solution and it doesn't work