Flat lining / no measurements

[Forest124]

I've had my KH10.5 and batteries for about two weeks and they've been working well.
Yesterday the installer came to install the PV solar panels and finished after sunset.
So had my first day testing them today.
It is now 5pm the next day and I've had a full day and there has been sun on and off.

However something seems off. All the measurements seem to be flatlining.
The load of 7W is not realistic. It is showing 0W Grid usage even though I'm using it. PV isn't registering any amps even thought he PV voltage is 520V as expected.

Usually the Grid Consumption line graph is very active and shows peaks of times of high usage. But now it seems to be flat-lining and doesn't seem to be showing any activity for the day. Even though I've had a normal day of usage (pool pump on, boiled kettles etc). The CT clamp does at least visually look connected as it was before.

Can someone tell me what could be wrong?

[Forest124]

Last night we had a rolling blackout and this drained a bit of the batteries to keep the house going.

This morning I noticed some action from the PV!
It seems the PV is being used to charge the batteries, but not for powering the house. Isn't that completely weird?

Yesterday my batteries were at 100% which is why it was drawing 0 Watts from the PV.

I can see the EPS watts for the house in the Inverter screen but Grid pGrid is always 0W. Wondering if this is all related to the malfunctioning CT Clamp / Grid Consumption monitoring?

[Dave Foster]

Important thing to remember the energy flow isn’t real time - it takes a single snapshot of all sensors every 5 minutes so it is difficult to work out instantaneous things.
The graphs give the better visualisation because they help smooth out the data points but you will get the odd strange point if the snapshot is taken just after you have turned a large appliance off when the inverter sometimes feeds in, or imports but only for a second whilst it rebalances it’s loads.

[Forest124]

Thank you. I was aware the app/cloud based website only update every 5 minutes, but one can see the information on the Inverter itself realtime though at least.
The issue is for the past 36 hours Grid Consumption line graph is permanently 0 all the time. Also pGrid on the Inverter is always 0W. Any ideas why?

I've also experimented a bit, and turned off my grid supply for a few minutes. It seems that the PV only seems to work to if there is no grid supply OR if the battery SoC is below 100%.
If SoC is 100% and Grid is on then 100% of my power is coming from the Grid.
Is that how it is supposed to work?

I thought that while the grid is on it was supposed to take as much energy from the PV as possible and only top up the shortfall with the grid, in order to save my electricity bill?

[Dave Foster]

Couple of things to check, firstly error logs, you can see the most recent errors at the inverter panel in History, Error Logs - is there anything in there recently and related to grid voltage, 10 min average fault ?

The second thing to check is your RVolt value, preferably on the website - there is a dropdown list on the lower graph which allows you to select RVolt, it helpfully displays the min and max, the maximum value is the one i’m interested in - is it high > 254V ?

You are correct that in Self use mode the solar should firstly cover the house load, then charge the battery before finally exporting to the grid.

As you say there sounds to be something wrong with the grid consumption / load and feed in measurements - the common item here is the CT clamp (I will assume you don’t have an optional Meter installed, but if you do read Meter_1p where I now mention CT). The CT is a white box like clamp with black cable which should be located on the smart meter live tail, can you check it hasn’t become unclipped/disturbed when the work was done a few days ago.

Also if you can check at your inverter that it has been enabled, you will find that in Settings, Feature, Meter/CT and this should be set to CT (not disabled), if it is disabled set it to CT and the inverter will restart and then should start correctly reporting grid / home usage.

[Forest124]

Yes RVolt is constantly around the 240V mark (apart from during the rolling blackout 4am-6am).
What does RVolt represent - I've always wondered!

While we are on that, perhaps you can also help me understand what TVolt is for? These are both cryptically named.

You are right that I don't have an optional meter installed. Only the CT clamp.

I found an error log which occurred at the exact time that my Grid Consumption line stopped working.
"Meter lost fault"
This is also the time the Installer was working on the system and hooking in the PV two days ago..
I do understand this implies that the CT clamp might have been disconnected, but don't know how to fix this...any ideas? Should I unplug it and plug it in again? I also am not sure if it was a temporary error or an ongoing error, as would it show when it was reconnected, assuming it was reconnected?

[Forest124]

Some charts at the time of the problem 18:11.

[Dave Foster]

Ok, voltage is fine - from what you have said and co-incidentally when the installer was wiring up your PV the meter (CT) was lost - I suspect as the CT wires go into the connector next to the PV connectors that the installer has disturbed the CT wires and one of the cores has broken away from the connector. This is quite common because the CT cable cores are very thin and break if the screws in the connector are over tightened, it only takes a nudge sometimes for them to break.

Next steps depends on how much you want to get involved, the easiest way is to ring your installer and let them re-terminate the cable (recommended), the more difficult way is for you to do it yourself, the connector is large and fiddly and would normally come apart with a special tool, but it can be done with a couple of flat bladed screwdrivers. - I’ll link to a thread where I posted some pictures recently so you can see what the connector looks like, the CT cable should be connected to pins 7(black core) & 8(white core).

On your comment on naming of RVolt is ‘Reference’ voltage - in this case the main grid, in 3 phase installations you have the R, then S (Secondary) and T (Tertiary)

[Dave Foster]

If you follow this link it will show you the connector and how it comes apart -

viewtopic.php?p=1028#p1028

[Forest124]

I knew when I read your post that you had to be right about the CT cable. Faster and easier to do myself then to call the Installers.

I opened the CT connector successfully using the flat screwdriver approach. I could not believe that the red wire had completely come out of the connection. For anybody else reading this, the CT wires are incredibly thin!
After this was wired in properly (and with care!) the Grid Consumption reading on the cloud site as well as the Inverter > Grid > pGrid value on the inverter itself started reporting measurements again.

Suddenly the PV sprung to life, after 2 days of it sitting doing very little except for keeping the batteries at 100%. It seems that the Inverter needs to know how much power is being consumed in order to work out if it should draw any power from the PV. Which kinda makes sense. All this rests on the CT clamp working properly, so quite a few lessons to be learned here.

Thank you for your explanation about (R)eference, S(econdary) and T(ertiary) in the extra graph options! So useful!
Now I can use the RVolt graph to accurately determine when my area is experiencing a grid fault!

On Sunday there was another grid fault (The substation had a problem) and my area/suburb had no power for a whole 8 hours! My PV and Inverter powered the house the whole time and I have never felt so independent. Such a blessing.

My next step is to setup HomeAssistant so I can have a bit more realtime information and also to extend my home automation. So any advice on where to start with that will be great.
I already have a RaspberryPi powering my own custom built HA.

This morning my battery is showing up as "Status: Offline". Not sure if this is due to the Foxess software update last night. Hopefully it will come right by itself.

[Dave Foster]

Well done , yes you’re right about the inverter, without the ability to measure grid consumption or load it cannot start up the solar without knowing where it can send the generation.

I think the off-line message is likely a problem with the FoxESS servers they have been under maintenance and appear to be operating erratically at best at the moment.