question

If it's not the firmware and it's not the check box that's not checked, what could it be ?

Is there a way to analyse the actual sequence of events in the MPII that leads to the error? The advanced data in the VRM seems to show it's not exactly the moment when the grid power came back on that the error occurred.

Or is there a way to disable error 24 ?

@Matthias Lange - DE It seems you're the man who knows about this sort of thing:

I have been through the official list of probable causes.

1. External current sensor is ticked in V.E.config, so not that,

2. Firmware is a recent version, so not that,

3. There is a large load connected but less than transfer switch capacity (load is 32A max) and as can be seen from the drawing, shouldn't be supplied through the MPII in the event of a power cut.

Have you got any ideas for a solution?

Sorry, I forgot to include the batteries in the diagram.

Sorry to make multiple posts about this but someone woke in the middle of the night to find all power out and their CPAP machine (a medical device) had stopped. The grid had actually reinstated itself but power to house loads (which passes through the MPII ) was blocked due to this error so we would like to find a solution if possible.

Thanks,

@usernamepasswordbs Why are you using both a CT sensor and a EM112? You're doubling up on the recorded grid supply recording, assuming the EM112 is connected to your Multiplus. One or the other.

I used to use the CT sensor but then as my Multiplus only powers the loads on AC-Out, I realised I dont need to use it so I disconnected the CT sensor and fitted a ET112 so I can see the loads before the Multiplus.

Depending on the information you want to display in the VRM portal and if you want the multiplus to also supply the loads before the Multiplus (Grid Loads), that would define what meter or CT sensor is best to use.

Link before to my VRM portal, in the photos I have a schematic of my system which shows the location of my ET112. Previously I had the CT sensor on my incoming tails.

https://vrm.victronenergy.com/installation/171934/share/db6807bb

The reason for using both is because the ET112 gives more accurate information to the VRM but unfortunately the response time when loads are switching on and off is very very slow, 20 seconds or so.

The ET112 is connected only to the Cerbo and it alone gives data for the VRM to record as far as I know. The CT is connected directly to the MPII as external current sensor which allows the MPII to react very quickly to load changes. Best of both worlds.

Having said all that, do you think that could cause this error ?

@usernamepasswordbs I cant see how you can use both as the data would conflict with each other. The CT sensor replaces the built in CT sensor so the moment you unplug it, it switches back to measuring the current within the built in sensor. If the Multiplus is recording the grid from the EM112, it thinks the CT it is measuring is the built in one. By using the external CT sensor, I think the Muliplus is measuring what it thinks is the internal CT sensor but it is actually measuring the grid, therefore giving the unit the incorrect data. I would unplug the external CT sensor, reboot the GX device then see what it going on.

If the problem still persists, then we can look further into it but that to me sticks out as a notable issue and a potential data conflict.

CT connected to multiplus wire type and plug in type ?

CT connected to Multiplus: wire type (3 pin plug with 2 wires from CT plus one empty pin).

ok not plug in type good

For the CT clamp don’t tick external, it’s still seen as an internal MP sensor, once you tick external you will stop getting measurements from the CT. Take off the CT without changing anything and see what happens, just been playing around with this last night too just to check my CT which works :( @Jason - UK

Thats Strange as even if my ET112 is wire to the grid and I isolate myself from the grid it does not shutdown the critical load and the multiplus continues to function as it should no errors it only displays no grid on the VRM which you would expect. This is with my CT disconnected.

I could try that but it must be said that one of the official causes of error 24 is apparently installing an external CT but NOT ticking the box in VE.config.

My system supplies the critical loads from the battery during a power cut as it should but when grid power is reinstated, the error occurs and all loads are cut and the battery just idles.

Monitor for grid failure: enabled. ESS relay test: completed.