After a complete reset, I configured my Multiplus II with ESS Assistant, ESS Mode 3, for controlling the power output externally. After a hard road to travel, setting the power output works.
BUT as soon as I connect the MPII to the Venus system, the Charge Voltage of all my SmartSolar chragers is set to zero (0) and accordingly they stop charging. This is certainly very counterproductive for a PV system…
This is usually only required in very rare situations. Not sure if you then would have to manually set the ChargeVoltage for the MPPTs.
Would try with one of the default modes and see if that already resolves the issue.
Edit: Yeah, according to the documentation, Mode 3 (External control) requires you to manually control Managed Battery Charge-Limits. So, if you don’t set them - they are probably 0.
#288 disappears when I disconnect the MPII from the system. #296 has almost the same objects and values as 288 but remains present when I disconnect the physical MPII. Both have
@alexpescaru I do not want the MPII to charge from grid. I hope this is the right setting. I changed that, but no influence on the ssolar chargers. they are always set to zero regardless that setting
@dognose I have a system running really fine with a Lumentree, commanded by serial communication. The only thing I got the MPII for is that I require more power. So in easy words I split my setpoint 1:2.5 to Lumentree and MP2
the MP2 should do nothing else than put out power. my control is highly sophisticated including everything I need and much more sophisticated than what the assi could do… (different behaviour on different change of loads, regarding pulsing loads, differently in summer or winter, …)
Well, hard to say how to do it different, without knowing your whole layout / system.
What I would probably do when running two systems parallel: Control one to desired Power (In your case the Lumentree) - and have the Multi automatically adjust for all the remaining / missing power.
If theres a second source, providing - say - 800 Watts of power, the multi will simply see 800 Watt less consumption and just take over the remaining loads.
You could also make this “explicit”, by injecting the Lumen as PV-Inverter in Venus-OS.
(I did that earlier with a second battery / fronius as well)
But yeah, as said without knowing the full system hard to say.
The one you just recently linked.
First you should check on the control of enable/disable chargers. Disabling charging will most likely also disable the mppts.
You want to avoid the multis charging, and that document says
The power flowing to the batter (or more precise: to DC system attached to the Multi) is equal to the AC-In power minus the AC-Out power.
Hence, you control the multis charging through that, not through the “Disable charging” flag.
Or in other words: When only connected on AC-IN, don’t set a negative AC-IN value, and the multis wont charge the batteries from grid.
sorry, I’m too blind to see - what document? The “ESS mode 2 and 3”?
as I said, I tried both settings for the charger but no difference in ChargeVoltage of the solar chargers. I will change it again now (enable charging). let’s see what happens…
by the way - I can’t read register 4921. always
regardless if I try reading from 239 or 100.
Is there another way to read Ess mode? (and perhaps write?)
