Question/problem: PV yield from an SMA inverter on the essential loads is included in consumption in the top-right dashboard in VRM.
Configuration: Home installation with two consumer units, AC in and AC out for essential loads. SMA Sunny Boy 3800 inverter from 2009, without a connection to the Cerbo. Connected to an energy meter with the role set to PV inverter and the position set to AC Output. Firmware version 3.79.
How can I solve this?
PS: I’m new here. This is an attempt to explain it as clearly and concisely as possible. If anyone would like more background information, etc., just let me know.
It’s a Carlo Gavazzi EM24 Ethernet meter without CT clamps. If you connect it the other way around, you’ll probably get a negative figure for production. I don’t know whether that’s intentional.
An SMA Sunny Boy 3800 from 2009 without Ethernet. I use the EM24 as both a grid meter and a PV meter. Perhaps the meter itself isn’t configured correctly? That could be the cause, or maybe it isn’t connected correctly for a PV inverter. It now registers it as consumption on the essential loads. The settings in VRM have been checked and are listed earlier in one of my replies.
No, I mean your battery inverter. Because if it is a MultiRS: There was a firmware release that had a bug with stale energy counters. If you have that firmware that would cause the system to never “see” any energy leaving acout, hence the only conclusion is (mathematically) that all ACPV is consumed right away. (Which would match your described symptoms)
No, for the Multiplus there was no such error, it happend for a certain release on the MultiRS, but was fixed already.
Then you should check the configured location of the pv inverter (acin vs acout). Having it configured to the wrong side may cause wrong energy flows (and consumption) to be calculated.
Ah, here’s the issue:
The EM24 is not supported for the dual function as it only has a single energy counter and will mess up the resulting counter with energy on both connectors.
The EM24 RS485 meter supports dual function, but using it in this way is not recommended. This is because energy accounting is done over the total of all phases, and the meter only has a single reverse energy counter and cannot accurately account for grid feed-in while also measuring consumption.
This might be the cutting edge. Did you connect the inverter to L3 of that meter?
To measure a single-phase PV inverter in a 3-phase system, connect all 3 phases to the grid phasing terminals (3, 6 and 9). Now you can chose on which phase you want the PV inverter by connecting the L1 line of the PV inverter to terminal 1, 4 or 7.
Note that it wont work, if you use the “L1 port”, but have it physically connected to L3. It’ll still count on the L1 Counter.
If that PV is reported to be on L1 while it is physically connected to L3, then what would happen is:
System sees 3000 PV Production on L1.
Multi on L1 sees 0 passthrough current, or even power flowing from acin to acout
That results in mathematically concluding 3000+ consumption on L1.
And for the same reason, you are probably seeing 0W on L3 consumption:
Multi on L3 sees a high passthrough current, but 0 PV on L3.
That’s mathematically -3000 consumption.
We can’t have negative consumption, so display a 0.
Thanks again, Dognose, for your reply. I’ve definitely read it and checked already. I’m going to make this adjustment, but I’d rather not do it myself. I’ll see if I can find someone to do it for me. The person who connected it for me has stopped doing that—they’ve retired.
