I'm finding it frustrating how there doesn't seem to be a way to log data from a Grundfos RSI over time. To get the data requires paying for extra and very expensive equipment, which I can't afford. I'm wondering if there would be a way to get the data using the RS485 connection, as I know this can be done easily using a modbus connection on Sunsync inverters, and I had some luck when testing it with one of them. (see SunSynk - Inverter Monitoring - Inverters - Power Forum - Renewable Energy Discussion)
There is an intermediary device that Grundfos sell which I found when searching for modbus communications. I think this means you need their intermediary device to be able to communicate via modbus? (using GENibus RS485).
I'm a bit confused what GENibus is. There is this other forum post (which unfortunately closed 3 days ago so I can't respond, as it seems like the person posting had success in getting the communication link to work ) Is Genibus a proprietary communication method? And the pages from the datasheet he posted were showing how to communicate using it? Perhaps it is a bit beyond me, but am I right in understanding that to make it work, he needed to buy the Grundfos software and pc link adapter, get the developer login to see/change some parameters, and connect his PC at the same time as the arduino? If that's the case, then the datalogging would require the presence of the PC, which doesn't seem especially useful?
Would appreciate anyone that can shed some light. I'm a newbie here, so don't have many forum rights, and am wondering if I'd be able to just private message the guy with the solution if I'd been around for longer...
I will do my best to help you as I managed to get it to work correctly while interfacing with the grundfos units.
Firstly, I scoured the internet regarding modbus/genibus etc. and in fact the i did not need any of the beforementioned.
Importantly you need to know the grundfos commands and the replies. I did not do data collecting on my project however you would be able to do so if desired.
I made use of arduino nano with rs485 transceiver connected to pins using the altsoftwareserial library. We designed a custom circuitboard for our usecase.
The communication was actually end the end normal serial communication which was then converted to rs485 via the tranceiver.
What device are you looking to interface to and I can perhaps point you in the right direction regarding the documentation that I have. It is hard copy though so i would need to take pictures/scan the documentation.
The grundfos software and developer login that i needed on my project was provided by grundfos technician in India if i recall. Basically i connected the pc-link and my project in parallel to the unit i was connecting to. I did this solely to view the communications in the software to confirm if what i was trying to send was being interpreted correctly. Once I had figured out the exact hex values that i needed to send etc. i did not need this communication at all anymore and then simply further tweaked my arduino code.
Really surprising that you didn't actually use or need any of the modbus/genibus protocols. If that is the case, how did you work out what to send to get responses? (for data collection, I would expect to poll specific modbus addresses for things like pump power, and motor voltage). Was it just trial and error, while looking on the pc link to check what was happening? (Seems like that'd take forever...)
We're looking to communicate with a grundfos RSI. We have a few different sizes (15kW, 11kW, 30kW etc.) but I expect the serial communication will work the same for all of the ones in the same range.
Good to know that the pc-link software isn't necessarily needed, but it sounds like it was quite important for troubleshooting! How did you end up talking with a Grundfos technician in India?! :')
) Is Genibus a proprietary communication method? And the pages from the datasheet he posted were showing how to communicate using it? Perhaps it is a bit beyond me, but am I right in understanding that to make it work, he needed to buy the Grundfos software and pc link adapter, get the developer login to see/change some parameters, and connect his PC at the same time as the arduino? If that's the case, then the datalogging would require the presence of the PC, which doesn't seem especially useful?