Solis inverter alarm

[Tinbum]

You say "reduce the max charge current". Should I have adjusted to Amps too, or instead of?
Thanks again for all your help.

Changing that will make no difference at all as the charge current is already very low at high voltages so don't alter it.

[Tinbum]

Hi JohnW, I would set the overvoltage value back up, 60v may seem too high but the battery will instruct the inverter to stop charging if the voltage is too high.

No, at that voltage the BMS would be destroyed- see my earlier attachment.

[MrPablo]

Hi JohnW, I would set the overvoltage value back up, 60v may seem too high but the battery will instruct the inverter to stop charging if the voltage is too high.

No, at that voltage the BMS would be destroyed- see my earlier attachment.

It would be destroyed, if the inverter was actually sending that voltage. The pylontech batteries set the max charge voltage over CAN as you know, the only real way the batteries could even see that sort of voltage is if the CAN messages were being disregarded.
About the only way that would happen if the CAN link was down and in that case, the inverter shuts down the charge & discharge anyway.

The issue here is that the charging voltage is sent by the BMS, you can change the equalizing voltage all you want but it's overwritten as soon as you leave that settings page.

[MrPablo]

I have to say, I'm not impressed with the Solis implementation of Pylontech batteries.
My results suggest that the actual voltage sent by the BMS is not used correctly, instead the inverter uses it's own battery DC voltage reading which doesn't always match and can't be calibrated (from what I see).

Additionally, even though a battery may request a certain charge voltage, the Solis will often overshoot it for a period of time which causes yet more issues.

As soon as I started using the SMA CAN protocol and setting the battery to AoBo, the inverter correctly uses BMS provided voltage readings.
The voltage overshoots by perhaps 0.1v at worst, compared to the 0.8v I saw with the pylontech protocol.

Of course, that's not possible in this particular case for John.

[Tinbum]

It would be destroyed, if the inverter was actually sending that voltage. The pylontech batteries set the max charge voltage over CAN as you know, the only real way the batteries could even see that sort of voltage is if the CAN messages were being disregarded.
About the only way that would happen if the CAN link was down and in that case, the inverter shuts down the charge & discharge anyway.

The issue here is that the charging voltage is sent by the BMS, you can change the equalizing voltage all you want but it's overwritten as soon as you leave that settings page.

Their are some inverters that default to their internals settings if communication is lost- I can't remember the actual make at this time though.

I've never used a solis inverter -can you actually see what the actual CAN settings are on it that's it's using?

I'd liken it to saying lets remove all speed limiters on lorries as the driver knows not to go above that speed. The setting is their for a reason.

[MrPablo]

Their are some inverters that default to their internals settings if communication is lost- I can't remember the actual make at this time though.

I've never used a solis inverter -can you actually see what the actual CAN settings are on it that's it's using?

I'd liken it to saying lets remove all speed limiters on lorries as the driver knows not to go above that speed. The setting is their for a reason.

Unfortunately the best you can see on the Solis inverter (this model at least) for requested values is that settings screen.
- Equalizing Charge = Max charge voltage from battery BMS (cannot override)
- Charge Limitation = inverter limit and can override
- Discharge current = inverter limit and can override
- Float Charge = not used
- Battery Overvoltage = max voltage at the inverter, can override
- Battery Undervoltage = min voltage at the inverter, can override and ignores value from battery BMS

Actual values are on the standard information page (no.3), example here:


Protection & alarm flags are shown in the Alarm Message screen.

I understand your point re. the limit Tinbum, I'd just caution against setting it to the value suggested by Pylontech.
As the inverter will use it's own DC voltage readings with Pylontech batteries, you could have 53.5v at the inverter, 52.5v at the battery and the inverter trips prematurely, requiring manual attention. I'd rather put in some headroom as the voltage is poorly regulated.
Like I said, it's a flawed implementation that makes no sense, and caused me to have 3 days of no battery power for the house whilst I was away on holiday.

[JohnW]

Thank you guys

I have done as you suggest. I'll let you know if it solves the problem.
If it doesn't, I'll call the guy that commissioned the system.

Thanks again

[Tinbum]

So you would actually need to watch the inverter to see what it was 'setting' the max charge voltage to!

Unfortunately their are to many 'bad' inverters out there.

As the BMS in a pylontech battery is physically damaged at 55v volts I would keep the overvoltage setting below that, but that's making the best out of a bad job.

[MrPablo]

So you would actually need to watch the inverter to see what it was 'setting' the max charge voltage to!

Yes, and the frustrating thing is this behaviour is by design based on selecting a Pylontech battery. Other protocols and it behaves as it should.

[spread-tee]

I have the same set up, Solis with a bunch of Pylon-techs, and get the same warning codes when fully charged . Also a couple of days ago we had an alarm on the master battery itself when the SOC was at 18%, after sun-up and a bit of charge the red Led went out and hasn't come back since.
Is this electronics just throwing up warning messages because the parameters are running close to the edge, or is there a real possibility of damage?
I would have to check but I think the voltage parameters are similar to Johns, and as with his it all seems to be working normally.

Desp