Hi Mattias,
Thank you for your input, but first step I need some help to figure out how to get data from the PowMr inverter into Home Asistsant.
The inverter has a RJ45 rs485 serial interface. with following pinout:
1: RX
2: TX
3: VCC
4: VCC
5: RS485-A
6: RS485-B
7: GND
8: GND
Would it be possible for example to extract the data from he inverter and transfer these to Home assistat by esphome or over mqtt?
Your inverter probably has a different wire scheme and wonât work with my guide. You need to find those settings in you manual, I canât help you unfortunately
I also use a epever tracer inverter and have to wire it differently to get data from it through my gateway, all info in the manual though
Hey all, just wanted to share my personal feedback on my latest SRNE / PowMr (POW-LVM3K-24V) setup.
I tried many ways and so far, those are the results:
- Probes and Connection type:
It appears the USB and the RS485 are tied to the same controller internally, and pulling both at once will create conflicts, as in if once port polls data, the other port is unavailable for that timeslot.
- USB:
iPow connection is stable on the computer, however data in the third tab is fractional, not direct reading (as in voltages readings can be *2 or /2 from real life)
Trying to read USB port through a VM connected to /dev/ttyUSB0 worked, but was highly unreliable, with half the readings not happening because âCommand unrecognized or invalidâ
Trying to read USB port from a RPi (to try sending over MQTT) under Raspbian failed 100% of the time. Port is detected, but for some reason, I had the âCommand unrecognized or invalidâ every single poll.
RS-485:
RS-485 through RS485-USB adapter : Works, but I didnât like it
RS-485 through ESPHome : Couldnât make it work
RS-485 through Waveshare : Worked 100% of the time
Final and best solution (for my use case and liking):
Finally, this is what I used, Waveshare 485 to PoE Eth âBreaker styleâ device and YAML config to poll each address I needed.
Note : I found that readings were⌠of average accuracy. Especially in the grey zone where your solar production is close to the inverter output. Most of the time, my panel would say â0Wâ, my battery discharge would also be â0Wâ but my inverter would output â100Wâ.
Note2 : I also find the internal SoC to be very badly implemented. It does not the battery capacity, hence I am suspecting the SoC is just a curve based on the battery voltage. For accurate SoC, I canât recommend enough getting a coulombmeter or even code your own SoC (probably what Iâll do next)
Hey Mattie, I also found some discrepency in the Panel measurements, especially when battery is charged. At that point, for example, I can use 200W from the inverter, but battery discharge would be 0W, but also panels would read 0W/0A. Which I believe is wrong, as it is set to PV Priority and assuming those 200W are indeed pulled from the panel. Also reading 264.
Does anyone ever solved this discrepency (by polling anther register or making home-made helpers to correct this offset?)