Introduction
In 2022 I had a solar photovoltaic and battery system installed in my house. This article lists a few things I’ve learned about the inverter in my system: the Solis S5-EH1P5K-L, the 5 kW variant in the S5-EH1P(3-6)K-L range.
Datalogger stopped talking to the cloud? Unplug it and plug it back in
Two or three times in the past year, Solis Cloud claims to be receiving no further data from the inverter’s datalogger. My system uses a Solis S3-WIFI-ST as the datalogger.
Turning the datalogger off and on again seems to fix it. There is a “reset” button, but that doesn’t seem to be enough; I had to physically disconnect it from the inverter entirely and then reconnect it. Solis Cloud should see data updates within 5 minutes.
As the S3-WIFI-ST article mentions, when disconnecting, take care to twist only the black connecting ring, not the silver casing.
My inverter’s real-time clock runs fast by two minutes per month
I expect it also doesn’t adjust for Daylight Saving Time.
I’m on a time of use tariff with my electricity supplier. I charge my battery from the grid during the off-peak time, using the inverter’s “Time of use” feature. If I were to set the “Time of use” schedule to start exactly when the off-peak time starts, the clock drift means I would soon inadvertently start charging during non-off-peak times. Instead, I leave 20 minutes lee-way, and resynchronize the clock twice a year, on the evening before Daylight Saving Time changes.
Installing the inverter in an accessible location is handy
When selecting where to install the inverter, surveyors commonly suggest a house’s loft. I opted instead to have it installed in my integrated garage.
The inverter is about the size of a microwave oven sitting on its side, has some chunky wires coming out of it, and needs some space around it for ventilation, so it is nice to have it somewhere out of the way (doubly so if you’ll have some batteries)
I haven’t converted my loft in to a living space, so getting around it is precarious: walking on trusses, with no overhead lighting.
Some surveyors gave the impression I would rarely need to access the inverter, but that’s certainly not been the case for me: reconnecting the datalogger, changing the charging schedule or the clock require physical access to the inverter.
Another benefit of garage versus loft: my garage is colder, which should increase the longevity of the inverter and batteries.
Check your inverter’s export limit is what you expect
In the UK, the system installer has to notify the DNO1 about any new system being connected to the grid. The process is slightly different for systems that have the potential to export over 3.68 kW back to the grid: the DNO may insist that export power is capped2.
In my case, the system was installed about a month before I got approval from the DNO. Consequently, the installer put a 3.68kW export cap on while the DNO application was in progress. The installer didn’t tell me they capped it, so the thought never occurred to me that I ought to increase the cap once I was notified of DNO approval, and I was inadvertently wasting electricity for a few months until I spotted the behaviour while looking at system performance charts.
For the Solis S5-EH1P(3-6)K-L range of inverters, to find the export cap, see
section 6.6.7 of the manual “Export power Set”. The menu of interest is under
Advanced settings > Export power Set > Backflow Power