SOC shutdown Also shuts down PV Input
Inverter, 5Kw (hybrid) applied off-grid, i.e., no Grid input, generator, wind turbine, nothing.
Battery settings:
► Shutdown: 23%
► Restart: 25%
► Low Bat: 30%
☼ The problem: The inverter shuts down both AC output and solar PV functionality when reaching Shutdown specification.
• My Understanding: Only the AC should be turned off until the "Restart" SOC is reached. One would assume that reaching the Restart SOC requires the PV Input, which in this case is off, so how does this inverter hope to recover without that function?
• Case Description: In my case, the inverter came out of the night into the morning and at 06h35 the Shutdown was triggered causing the AC to terminate. The sun was already delivering 5W at 05h17 and the point of Shutdown was over 100W. So, PV Input happened that should have caught up the battery charge soon enough. The start-up voltage for the 5Kw Sunsynk model is 150V, which it had. However, the PV Input was shut down along with the AC.
• Possible Solutions: I suspect there must be a setting that governs the duration of any shutdown on the MPP controller, or that (perhaps) because it is a hybrid inverter it assumes a problem with the PV Input and fails the source in favour of Grid Input, which after a while it's not getting and therefore reverts to solar.
→ This timeout period (where the PV Input is not being accepted) can be anything from 30 minutes or upward of an hour.
ChatGPT suggested looking for two settings, 'Back to Grid Voltage' and 'PV Restart Voltage'. However, Google could not find the explicit search [sunsynk "PV Restart Voltage"]. The Sunsyk application has a setting under Grid Settings called "Reconnect Ramp Rate" (set to 0) and "Reconnection Time" (set at 60s) and a lot of other settings I have no idea about. If the Grid functional aspect of the inverter is the cause of this PV Input timeout, can it be set to "off" or something to avoid the inverter relying on it to recover, but keep on using solar as the primary and only source?
This is a senario that I had never tested.
After testing to see if the SS inverter bahaved as you described, I have to report that the inverter does work correctly.
The inverter did shutdown the AC generation as expected when the shutdown voltage/percentage was reached and the PV did also stop charging the battery, but after about a short period (approx a minute) the inverter did start charging the battery although the System Flow Chart does not show that the battery was being charged. However the battery voltage was increasing and using a clamp meter I confirmed that charging current was going to the battery. When the Restart voltage/percentage was reached the inverter srted AC generation.
So the only issue I can see is the the System Flow Chart does not show that the battery was being charged. I would suggest that this is a bug.