Getting Data from Solis Inverter

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144

In general terms, no.

The inverter is a slave (server) and the sick is a master (client). You can only have one master on an RS485 Modbus line - hence one stick or one RS485 adapter.

RS485 is just a serial comms, and it has no inherent ‘address’. Everything wired in get the same electrical signal.

That said, you can wire in anything you like - including a stick and another RS485 adapter. Trying to use both at the same time will however almost certainly generate data collisions on the bus - particularly if you are trying to do writes.

The way I got around this was by using a special tri-port adapter which was specifically designed to deal with dual-master Modbus setups. It did work, but in the end my Solis data logging stick did not, so I gave up and now run everything from my HA without any Soliscloud.

There are other posts I have seen where the use of an intermediary arrangement allowed for the RS485 adapter to work as master to the inverter, and to on-send data to the logging stick as a separate client-master link.

145

S2-WL-ST + S5-EH1P6K.
Build details here: Successful build: S2-WL-ST + S5-EH1P6K-L - cost effective · alienatedsec/solis-ha-modbus-cloud · Discussion #24 · GitHub

146

I have been following this topic closely, as well as other places, and have finally taken the plunge.

I have chosen to use a TSH-735 RS485 bus sharing device in order to have two Modbus masters on the same bus. So my HomeAssistant is a master and so is the datalogging stick.

This does work. Well, most of the time. I am still receiving nonsense responses from the Solis inverter about 1/3rd of the time.

I’m aware that comms settings may be crucial to the reliability of the comms. Can anybody here who is successfully using a TSH-735 share all of their TSH-735 settings on this forum?

Regards,

Julian

147

I stopped using my TSH-735 over a year ago. Finally gave up trying to get my data logging stick to work, so I stripped this all out and went to direct RS485-ethernet adaptor connection (which works very well and I personally can’t see any benefit to keeping the stick).

I had to refer back to my old picture of my hardware to recall which port was which.

Managed to fire the old unit up, and here are my settings as they were when last in use. I did not find much issue getting it going to start with. But I did have a higher Baud rate on port 3, and I did use the monitor and saw a few problems, so adjusted all Baud rates down to 9600 to match the inverter and stick, removed the read-cache on the stick port, and tried different settings for the Ignore Frame/buffer error settings.

I did check timings and tried different settings for the Slave Timeout, in the end settling on a high figure as this seemed to be better.
I was a little suspicious of the read-cache, and I assumed that repeated reads to the slave for the same register would return the cached read rather than going back to the device, but never managed to see much difference.

Like you, I did see a proportion of Modbus read errors. Forgetting to put back the terminating resistors after a bit of rewiring did not help. I was in the process of using the inbuilt monitor to try and adjust various settings (without seeing much difference) when I decided to stop using this, so I never quite managed to obtain the ‘best’ settings.

I now use a direct connection via a Modbus aware RS485-ethernet adaptor. Polling a large number of registers in multiple blocks of 50 (maximum recommended read size) every 20 seconds, I still get about 20 read failures each day, so I don’t think that I will ever get this error-free. The inverter is probably quite busy running itself to always manage Modbus as well.

Hope this helps.

Application Mode:

TSH735 mode
TSH735 mode923×737 47.7 KB

Port 1 (The inverter as Slave)

TSH735 port 1 inverter slave
TSH735 port 1 inverter slave933×663 54.2 KB

Port 2 (The data stick as Master)

TSH735 port 2 data stick Master
TSH735 port 2 data stick Master933×679 54.2 KB

Port 3 (Ethernet converter to HA Node-RED as Master)

TSH735 port 3 to ethernet HA master
TSH735 port 3 to ethernet HA master931×699 56.3 KB

148

Thank you. It’s good to know I am not alone!

149

I have a st-2 stick so port should be 502. but I can’t get the data. Which ip adress schould I use. when I connect to the network it shows me a ip adress but that one doesnt work. I really dont know what to do anymore.

150

First step would be to update your inverter to the latest firmware, some old firmwares do have issues with modbus. Best would be to contact support.

If you enter the IP in your browser, you should see the inverters basic webview, if not, the ip is incorrect. Also, IPs are specifix to your network so cannot help with that

151

yeah I can login to the network. But should it be connected to my home network? and if where can I find the ip adress once it is connected?

152

The inverter, and device running homeassistant should be running on the same network. Once again, getting IPs is specific to your network.

You can use a tool such as Fing on the playstore to see all ips on your network.

But remember to get the firmware upgraded

153

thanks I found the ip address. it still won’t pull the data.

How did you update the firmware. Because I don’t have a datalogger with USB port.

154

Best would be to contact solis support, they are extremely helpfull and quick to respond. They will most probably push the update over the air, or they will provide you with a file and instructions.

155

great thanks. I will get back to you when I contracted support.

156

I contacted solis support. they would’nt update my inverter because there was nothing wrong with it.
Could it be that HAS is not pulling data from the converter because it’s signal strengt is to low? There is some distance and walls between the inverter and the router.
Would it helpt to connect it via a ethernet cable to the router?

157

I succesfully connected the datalogger to HAS. But all the entities show a value of zero. What could be possible causes of this?

158

It’s best to open a ticket on the github repo, it’s easier to follow, and investigate from there. There might be multiple reasons, but I can almost guarantee you, it needs a firmware update.

Are you able to paste a screenshot from your inverters web ui? That should contain the info needed to determine if it needs an update.

159

I opend a issue in the GitHub. I also added the screenshots from the webpage.

160

Hi all,

First off, this looks like the best thread for a Solis Inverter related system question, but if it should be it’s own thread or I’m in wrong place, my apologies. Please point me in the right direction. I’m happy enough to be moved or to repost elsewhere.

I’m about to take the plunge on solar and wanted to make sure I’ve got my ducks in a row before my duckets as it were. :slight_smile:

The installer is offering a Solis S5-EH1P(3-6)K-L and is willing to do the RS485 wiring if I take care of the software setup for Modbus. That seems like a good deal to me since if I do the wires they’ll go everywhere, and he’s promising to keep them all neat and tidy.

I have three questions:

  1. Are there any gotchas I need to be aware of regarding this model inverter and modbus? Anyone done it?
  2. The battery the installer is using is a Rosen Powerwall LiFePo4 (Model: LFP48V200AH). I’m not finding anything about these anywhere. Anyone hooked one of these up to Homeassistant? Are batteries pretty universal?
  3. There’s a LOT of different info and approaches as I’m researching. This (GitHub - alienatedsec/solis-ha-modbus-cloud: This repo is a workaround for Solis inverters to connect Solis Cloud and the local Home Assistant regardless of the model of your Solis datalogger) looks like the most up-to-date and comprehensive solution to me, but is there something else I ought to have a look at instead?

Thanks so much for your time and sharing your thoughts!

161

In my humble opinion (as an owner of a Solis / Pylontech setup) …

Solis are a large, world wide manufacturer with significance market placement. They provide industrial units for large solar farms. “Popular”, and “successful” come to mind.

I believe there is an inverse relationship between the market size/dominance of a manufacturer (any market) and the company openness and support (particularly for the little domestic customer).

[code for - great product, but…]

Do expect a ‘good’ product. Don’t expect easy connection, or easy access. Read access to Modbus is available if you can get around the latest (they change often) protocol / physical connection / register map. This, I believe I am fair saying, is not a plug and play device (whichever model you have).

Your battery looks much like any 48 volt, and will (hopefully) have a dedicated entry in the Solis inverter battery table. That sets all the (highly critical) control values to something appropriate for a 48v Lithium unit. As such, these 48v batteries are ‘universal’. As to ‘hooking up’ to a battery, you don’t. Batteries and inverters have an interesting relationship - the battery BMS looks after the battery, the inverter controls the battery charge / discharge, but actually the battery tells the inverter what to do.

Your battery has CANbus connectivity, and RS485. I would expect the CANbus to be used to connect battery (BMS) to inverter. This is one way with battery shouting at inverter every second with charge limits. Inverter listens and controls the battery voltage to direct charge / discharge. Connecting to this is limited. You can listen in, I do this by listening in on my Pylontech CANbus. It is interesting, but you certainly should not be ‘controlling’ the battery this way. Big NO!

The RS485 is probably a backup inverter control, but may well have a very complex command sequence. Interestingly no RS232 comms, so no ‘console port’, but perhaps the RS485 is a console comms port? Whatever, you probably DO NOT want to be doing anything with the battery anyway. You ‘control’ the battery by ‘controlling’ the inverter (mode / charge limits etc).

Yup. Solis, in my limited experience, change things about every 9 months. I have been using my Solis for 3 years, hence the logging stick has gone through three or four iterations, the protocol two or three, the cloud site a couple, and so on. If you want to stay ahead of the competition build a great product, keep on innovating, and keep changing things.
My suggestion would be, go with a market leading inverter, accept what your installer provides, start experimenting to see if you can connect, build on your successes, setup monitoring first and control later, get it all working as you want. Just don’t expect someone with a Solis inverter older than yours to be of any help, or anyone with a Solis inverter newer than yours to be of any help, because SOLIS KEEP ON CHANGING EVERYTHING about every 9 months.

Yup - great product, but…

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162

@t3d - I have a similar setup and followed the alienatedsec approach with good success: Successful build: S2-WL-ST + S5-EH1P6K-L - cost effective · alienatedsec/solis-ha-modbus-cloud · Discussion #24 · GitHub
No gotchas.
Type of battery isn’t really relevant to this setup - all integrated via the inverter’s data logger.

1 Like
163

Thanks, @Biscuit! This is really helpful. I appreciate your detail and clarity. That gives me a much better understanding of what I’m stepping into! And what I can reasonably expect to be the challenges.