Cannot get an answer from Wattcycle - unless they answer this post - so hoping someone here might know?
Who manufacutures this BMS?
If it's a TDT bms, how was it modified? If I knew, maybe we could obtain a proper manual and correct RS485 pin out instructions. Maybe even new firmware, PC to Can wires, and actual support.
Is a CAN or RS485 "resistor" needed to enable comms? If so, where do you get it with instructions?
Are RS485 comms actually supported at this time? We cannot get the battery to communicate with any other battery, with any inverter, nor with a Raspberry Pi and Solar Assistant.
We cannot change the pack address and the pack addresses do not automatically switch.
Is there actually a protocol on board that actually works with any inverter?
I'll try anything at this point.
What particular inverter model are you using rather than trying to address every inverter? I think you need to match the battery versus the inverter comms. I have an Eco-Worthy inverter with RS485-1 and CAN/RS485-2 ports and the inverter manual direct to use the CAN/RS485-2 port for battery communications as the inverter RS485-1 port is for RS232 tech diagnostics. And to use the supplied inverter ethernet cable or a specific pinned cable described in the manual. In other words, an off the shelf ethernet cable will not work.
So my Eco-Worthy inverter prefer RS485 - Pylontech comms while the WattCycle battery perfer CAN - Victron. I set the WattCycle battery to CAN - Py/MEG/Dey and the battery - inverter communicate just fine for me.
I just received mine and am trying to connect to the BMS with RS485 but can't get the panel LCD to make the settings change from CAN to RS485 - there's no confirmation or save button! and nothing in the app.
I just commissioned a system with 10 of these server rack batteries connected to a Victron Cerbo Mk2. It took a fair bit of troubleshooting, and was only finally resolved thanks to @TBone Blade 's note about a custom ethernet cable.
Notes:
- There is no 'supplied' inverter cable, except for the small jumper cables
- To make Victron comms work, you need a special RJ-45 Cable. Victron sells this as a VE.CAN to BMS cable, Type A (P/N ASS030710018)
- I didn't have this cable, but I have the tools and know-how to create a custom RJ45 cable, so I did, matching the CAN-H, CAN-L and GND pins on the Victron VE.Can port to the respective pins noted in the WattCycle manual
- WattCycle batteries are set to "Victron"
- Victron VE.CAN Bus 2 is set to "CAN-bus- BMS LV (500kbits/s)"
- There is a Victron termination resistor in the othe VE.Can Bus 2 port
- The battery bank is now visible on the Cerbo, and it reports as a 'Revov' battery (which I think answers the BMS question).
- One last note - these batteries (and many similar server rack batteries) do not report Capacity (Ah) over CAN bus in a way that Victron can read. Therefore the Cerbo reports SOC, but it will NOT report 'Time to Go' (days, hours, etc). Just something to be aware of.
I think the major take-away is that anyone trying to connect these to a Victron Cerbo will need this non-standard RJ-45 cable.
