Monday, we had a power failure on the net. This resulted in errors on the Multi RS and a short power failure on everything connected on the AC-OUT.
What could be a reason for this as I would have thought the victron system would stay online and disconnnect the AC-IN, in such an event.
More information about the system.
VM-3P75CT
3x Multi RS solar 6000 (solar input not used)
Cerbo GX mk2
Lynx smart BMS
2x Lynx distributor
4x 16kWh LFP with JK-BMS
Kraus & Naimer KA63B
More information on how it’s connected.
3 phase powergrid → VM-3P75CT → Zaptec Go 2 charger → AC-IN Multi RS → AC OUT Multi RS → distribution board → AC connected Enphase solar panels.
Batteries were charged to 30%. Load was 3000W and solar was generating 4800W. Some of the excess was send to the grid when the powercut happened.
It seems to be reporting overloads and excessive current alarms.
More likely your PV inverter didn’t throttle properly so the system shut off.
You would need to generate charts showing the individual phases, PV generation etc.
But the RS is quite sure you tried to force more into it than it is designed for.
In a working system, yes, hence the factor 1 rule.
A full battery, and a DIY one, can add variables when having to sink a lot of power unexpectedly, and can also result in overloads.
Err 50, Err 52 - Inverter overload, Inverter peak current
Some loads like motors or pumps draw large inrush currents in a start-up situation. In such circumstances, it is possible that the start-up current exceeds the over current trip level of the inverter. In this case the output voltage will quickly decrease to limit the output current of the inverter. If the over current trip level is continuously exceeded, the inverter will shut down: wait 30 seconds and then restart.
The Inverter can supply more power than the nominal power level for a short time. If the time is exceed the inverter stops.
After three restarts followed by another overload within 30 seconds of restarting, the inverter will shutdown and remain off. To restart the inverter, switch it Off, then On.
If the error persists reduce the load on the AC out terminal by switching off or disconnecting appliances.
I can’t say I feel positive vibes when enphase and modbus is mentioned in the same sentence.
It’s a worst case scenario if you have a full battery, PV is pumping, exporting power and suddenly the grid takes a vacation.
A lot of power suddenly needs to find a home and if it doesn’t get this right then bad things can happen.
The graphs aren’t showing any peak production or usage. So don’t know what graphs I would need in such an event.
The battery was only for 30% full and the system isn’t near 1:1 rule with the solar panels. I will simulate a powergrid failure when the solarpanels are exporting to rule out the solarpanel export.
And Enphase with sunspec isn’t working at the moment. Opened a case with Enphase for this and tagged along with somebody having the same issue with Enphase and modbus/sunspec.
Why did you not connect all solarpanel’s to the RS 6000?
Did you test the system with grid disconnected?
I’m a electrician, at my juction box i have 2 one fase bypass switches, to wire them i had to think realy hard because it’s so different then simple switch, a 3 phase bypass is more dangerous because of hazard of mis-wire the netral and get 400 volts on every power socket.
Btw, I had all my solar panels on a 3 phase Fronius inverter, now they are all on one RS 6000, works like a charm. (The fronius wasn’t compatible)
The solar is distributed over 3 phases. I would have guessed the delivery to the powergrid would go to the batteries, but I guess this change couldn’t go this fast.
The Kraus & Naimer is the bypass to disconnect the victron AC-OUT from the house distributionpanel.
The solarpanels got placed in 2022 and are on the house. The victron system is in the shed. There is no way to connect them together at the moment. And yes we have the 3phase Enphase Q-relay.
Don’t have any problems showing in the graphs as a mis-wire.
Ok so solar is installed on the roof and I guess that the Enphase Envoy/Q relay are installed near the main switch panel. You have cables to/from your shed. How long are those and what size?
I’m assuming here that the Q Relay cuts solar power, before the inverters switch power. At that time there is no more power for the loads and the inverters need to step in. No idea what kind of load, but it was enough to trigger that error. And here comes the cabling to/from the shed into play.
You may try to reproduce this by pressing the test button on the Q relay on a bright sunny day. Note that some pieces of hardware might fail after a power cut. Notorious is the Huawei PON device for fiber optic Internet. So you have been warned. By the way. A tripped RCBO has the same affect.
The q-relay is near the solar panels in the loft. There it goes to a sub distribution board to then be taken to the main distribution board downstairs over 5x2,5mm2.
The cables from and to the shed are 20M. The AC-IN cable is 5x6mm2. And the AC-OUT is 5x10mm2.
They both have their own RCBO on the feed-in and main breaker on the feed-out side.
I would have tried testing with bringing down the main grid feed in. But the battery is always being charged. Will disconnect the solar by testing the q-relay. Hope this goes well.
No potential problems on IT load as the main parts like servers, modems and switches are behind a separate UPS.
