I have a 5kw Sunsynk inverter and 2x 5.32 Sunsynk batteries. I've connected my inverter to Solar Assistant via RS485. I have taken the plunge and replaced my Waveshare USB to 1 CH RS485 with the Waveshare USB to 4CH RS485. Setting up for the inverter was a breeze.

From  to 

However, I'm battling to get my Sunsynk batteries connected. I've set it up to be on ACM2 (3rd channel) as I plan to get another inverter, which will be on ACM1. Dip switched 1&3 are on, while 2&4 are off. 

I've followed the information on https://solar-assistant.io/help/battery/sunsynk, using a only 3 wires in a CAT5, on pins 1-3, and it is plugged into RS232 on the master battery (I have 2x Sunsynk SUN-BATT-5.32)

CAN is connected to the inverter and RS232 is connected on the WaveShare (which is RS485, I know). 

And I've seen other people use this 4ch on Sunsynk systems.

Can someone perhaps tell me what I'm missing? Should I have a splitter in the CAN?

(PS. The terminal cover on the positive was replaced, I took the photo for another reason)

@DannyBoyZA,

I may miss the mark completely, but why are you plugging a RS-485 port (from Waveshare) to an RS-232 port.

I would just try and plug it in the master batterie's Link In port. 

AFAIK, these link ports on all batteries are all RS-485 ports, no matter what the label says.

Typical for most Inverter/Battery/Management setups should be something like:

Inverter to Battery - CAN

Inverter to Management System (SA or HA) - RS-485

Device (typically a battery) to Monitor or Management System (SA or HA) - RS-232 using appropriate cable

Seeing you are doing everything Management wise via RS-485, you should also use the RS-485 port (the Waveshare device)

Keep us up to date, so we can all be in the know! 

14 hours ago, Sidewinder said:

I would just try and plug it in the master batterie's Link In port. 

Thanks @Sidewinder, I'll give this a go tonight

Hmm, a brief look at SA website doesn't state whether it's using RS485 or RS232. I fear that it may be using RS232 in which case your Waveshare won't work. 

Another option is to access the RS485 connections available on the CAN port. You'll need to create a custom cable, much like is necessary on the newer 5kw sunsynk inverters to access diagnostic info. Unfortunately I'm not sure SA is set up to use this connection. This is from the Sunsynk battery install manual:

@JaseZA,

Yes, that (RS-485) port is available, but it only spews out Inverter Data. The Battery Data it does provide is an aggregated view from the Inverter perspective, so pretty much useless. SA does it a bit better, with the appropriate USB/RS-232 cable, but it is very limited in what it does display. The Battery spews out a lot more info of value than what SA provides back to the user. Make no mistake, SA is very useful, but it is very limited in how/what it displays information, with very little customization possible.

This is why I use the SmartDeyeDongle (RS-485) with HA, with USB/RS-232 cable to the (master) battery, so I can see what I want/need. 

Oh, and Yes, this combo port is how SA get's the data, but I found that using the splitter does corrupt the RS-485 data, so I've solved that by crimping both cables into one RJ45 plug. 

Okay, makes sense that limited info is available on RS485 - means unfortunately RS232 is the only option. You say you use the SmartDeyeDongle but that is only RS485? Or are you using that in addition to an RS232 cable to pull battery data to a separate computer/Rpi?

I too had much better luck crimping two cables into a single RJ45 connector for my Sunsynk inverters.