How to use MultiPlus 2 as pure inverter, setpoint remotely controlled? (2nd try)

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I don’t think it’s possible to entirely get rid of the jitter around 0; there seems to be internal delays to acting on a setpoint change. I know about the 400w/s ramp time limit, the only way to resolve that I guess would be to change the grid preset but not going to do that (Perhaps might for a quick test)…lol

How are you getting on with this?
I came looking for help on MQTT - Seems to sleep in MQTT explorer, but comes alive if I open the VRM portal… Very odd…

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@dougle03 I think the 400W/s apply on the ‘grid side’ of the current sensor. on the ‘inner side’ the MP controls much faster even for sure it can’t be infinitvely quick. Certainly some jitter remains but using the current sensor it is much smaller than if using e.g. a grid meter and the loop over the ESS/GX or own control.

My next plan after mounting my ‘winter panels’ is to test the control via external current sensor. I tried my horribly-switching-load espresso machine connected to AC-out and the result on AC-in was great. So next step would be to put all hard-to-control loads on one phase and put the external current sensor on the same phase (next to the grid connection point) and use the ‘grid meter control loop’ for compensation of the loads on the other phases.

One challenge will be to ‘balance’ the setpoints of my two inverters, since what the MPII does caused by its ‘inner loop’ (the current sensor loop) will not be available for the ‘outer loop’ (my external control loop) and vice versa…

What is your problem with MQTT? you know that you have to write “1” to topic “R/b1234567890d/keepalive” regularly to keep MQTT ‘transmission’ alive?! I send every 30 seconds.

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I’m using a slow CT via wifi, so that’s deffo not helping, but my inverter is too far away to directly wire a CT coil to the MPII. I’m working on making it quicker to respond, but to be honest, the slight jitter is not too much of a problem. I have an automation in NodeRed that continually adjusts the SetPoint based on house load/generation, so I’ve offset that by 40 watts to ensure that I’m nearly always exporting a little (My goal is no import, rather than zero export).
Sounds like NodeRed could help with the maths when setting the phases setpoints perhaps? MQTT is certainly fast enough I suspect…?

Thanks for the info on MQTT, I had my keepalive configured incorrectly, all sorted now. :+1: I had it as you said, sending a payload of ‘1’ but turns out, sending a null payload was the solution for my setup - Have no idea why :man_shrugging: