Judging from what I have read on the forum, this may be an observation rather than a question, but here goes.
I recently was delighted to have found a way of using the 'general flag user' and 'programmable relay' assistants so that my house ESS system would connect to the mains at night to charge the batteries (cheaper electricity) and disconnect from the mains during the day automatically (ie ignore AC input). (Previously I had been disconnecting the mains manually with an external isolator.) It appeared to be working perfectly whilst I was away for a week. The fact that the PV was generating 0kWh did not bother me because my PV panels in the north of Scotland usually do that in the dull weather we were having. When I returned home I noticed that the kitchen appliance clocks had started to run fast. I also noticed an error code on the PV inverter which had shut down with a high AC frequency fault condition. Sure enough the AC frequency graph from the Multiplus 2 was as shown in this screendump.
The PV inverter screen shows the frequency cycling up to 52.4Hz approx 2x per minute.
When fully isolated from the mains manually the same graph looks like this.
Q&As elsewhere on the forum seem to indicate that this is a consequence of the inverter constantly readying itself for possible reconnection to the mains/generator, which would suggest that this characteristic is built into the control software and has no solution. BUT - just in case, there are some real clever guys out there, I am asking - does anyone have a potential solution to this? Switching the mains off during the day is not essential, but is highly desirable in my set up. And using this gives me the option of easily connecting the mains via VRM dashboard remotely which could be very useful during the summer months. It seemed a very useful addition to my ESS scheduled charging facility.
Thanks in anticipation,
David
