Battery idle after EV charging

We recently bought an EV and Zappi (MyEnergi) charger, to link up with our existing PVs and 13Kw of battery capacity. It has taken time to synch the EV with the charger but we have an issue with the battery. Every time the EV is charged we have to reset the battery to default as it stays in 'idle' mode after the charging is complete, even though the battery should be discharging. Otherwise the battery is working fine. Can anyone advise as at the moment this system is requiring more management than anticipated.? Thanks in anticipation.

GordonWilson need more info to provide advice.

What kit you got

How is the EV charger and house wired up, e.g. CT clamp of the inverter - can that monitor the car charger and house, or just the house?

How are you pausing the charge/discharge of the home battery when the car is charging?

Etc

Hi TX200

Thanks for getting back to me.
There is a CT clamp to the EV charger fuse box which is located between the main cut off and the smart meter while the battery CT is situated between the meter and fuse box. I am no electrician but I believe these can monitor both the charger and house.

When the charge goes beyond the set limit we are going onto MyEnergi Zappi app and setting it to stop. After that is when we have the issue with the battery staying in idle mode.

Regards

Gordon

GordonWilson From what you have described, both the inverter and the EV charger CT clamps are fundamentally measuring the same current flowing in or out of the house. The fact that they are either side of the smart meter makes practically no difference.

The problem with this is that the inverter will see the import coming into the house to charge the EV as being house load and will discharge the battery to meet it. Not what you want at all. If you are charging the battery at the same time as the EV then this mitigates it to some extent, but its not the best solution.

Better would be to have the EV wiring done in such a way that the inverter doesn’t see it as house load at all.

something like this:

Grid —- Meter —-X—-Inverter CT—-House fusebox
|
Car charger

Where the EV CT Clamp is doesn’t really matter too much. If its on the grid to meter connection then it can charge on excess solar being exported if that’s what you want to do.

When you are charging the EV what are you doing with the battery at that time?

GordonWilson synch the EV with the charger

There shouldn't be much to do between EV and chargepoint .?
Are you signed up to intelligent octopus go tariff, or going with something else? The extra cheap-rate slots with the former can make scheduling the GE system a little complicated.

Hi

Thanks for the feedback. As we charge the car mainly at night the battery has little house load to meet. What I have done is set the battery operating range to say at 85% allowing some use but ensuring the battery does not drain when the car is charging. It is in the morning that the battery remains in idle mode.

Regards

Thanks for getting in touch. We are Octopus Intelligent Go customers. Do you have a setting that works for you?

Regards

GordonWilson Thanks for the feedback. As we charge the car mainly at night the battery has little house load to meet. What I have done is set the battery operating range to say at 85% allowing some use but ensuring the battery does not drain when the car is charging. It is in the morning that the battery remains in idle mode.

How precisely have you set the battery operating range? I am guessing you have set the battery reserve to 85% to prevent it discharging to the car.
I think however you are setting the battery to stop discharging to the car is what's causing it to be in idle mode in the morning.

I suggest the better solution instead of using battery reserve is to set Pause mode to Pause Discharge and put a start and stop time of when you will be charging the car. You can't set the battery pause mode in the app but you can do it in the portal.
The inverter will remain in Eco mode but stop any discharging during your required period.
You can still charge the battery during the Octopus Go period as well if you want to.

geoffreycoan You can't set the battery pause mode in the app but you can do it in the portal.

Actually, you can do this on the app: configuring timed-discharge from 05:30 to 23:30 actually implements pause-discharge from 23:30 to 05:30

GordonWilson Do you have a setting that works for you?

Because the export price is (over) twice the overnight import price, my regime is charge battery overnight during the cheap rate (which automatically disables discharge), and then use the pause timer during the sau to pause charging, so that all solar is exported directly, rather than touching the battery. (It's slightly more complicated than that, with measures to avoid clipping and to avoid export if Octopus decide to charge the car outside the usual cheap rate, but that's the gist of it.)

Hi Apologies, I wrote a reply and thought I had posted it earlier. Appreciate all the comments.
My app and portal have the following modes;
Eco; Timed Charge; Timed Export; Battery Options and Reset to Defaults. I assume you are referring to the Timed Charge when talking about the timed Discharge as the Timed Export empties the battery very quickly. Can you clarify what you are referring to in Timed Discharge?

Appreciate your patience.

G

GordonWilson Timed-discharge is a mode offered for some inverters. It used to be made available for all inverters, but GE now prevent it being shown on inverters that don't support it
If you visit https://givenergy.cloud/ in a private browser window (which should hide your normal login credentials) you can connect to the demo dashboard.... oh, that doesn't have timed-discharge either. Well, you can see it on https://community.givenergy.cloud/d/3650-understanding-the-settings-on-your-app-and-portal then

Timed-discharge is to allow you to choose when the battery covers house load. At other times, it inhibits battery discharge. A bit of a niche option, really - useful perhaps for this with a small battery who want to use it only during an expensive peak afternoon tariff rate.

As you say, timed-export will discharge your battery at a fixed rate - usually for those that want to profit from a peak-rate export tariff.

Anyway, it appears that your inverter doesn't offer the timed-pause feature. Instead of setting the battery reserve to be high, what you could do is configure it to charge from the grid overnight, at the same time as the car, but if you don't actually want to import from the grid, just set a low target charge level. That should effectively idle the battery for the charging period, rather than actively charging. Eco mode should then operate normally outside of that charging period.

As mentioned above, another way to get around problems of GE discharging to car is to wire up the CT clamps suitably. See https://community.givenergy.cloud/d/4677-installing-2-hybrid-gen3-givenergy-inverters/9 for my recent post on how I got the wiring altered.

Thanks again for the comments. I will take some time to consider them.

Regards