Very timely video as I'm just adding a battery/inverter to my system. There may be a simpler way to implement your hard wire approach, which I am considering. Simply ask the electrician cut the copper bus bar inside the consumer unit that links the Zappi breaker to the Inverter breaker. Reconnect them with a loop of cable, but run this loop outside the consumer unit, making it possible to fit the Inverter CT.

This is what the export margin setting is for. For anyone with this issue, get the installer to set the Export Margin properly before having it rewired. Also make sure your kit has v5 firmware as there was issues with Export Margin on the previous v3 firmware. The rewire trick does work but is more hassle now that firmware has fixed the issue. I had exactly this and was on the beta testing of v5 and it works great now. Depending on your inverter, it can be a bit hit and miss trying to work out what the export margin should be, but start at 50w and increase it until you see the battery not getting drained. For me, I think I settled on 150w on my Victron inverter. You are aiming to get a value as low as possible that the inverter doesnt normally export to before its real excess solar. Inverters will always flip flop a little around the import/export point to some degree, you are trying to find what this usually is with no excess and then set it a little higher on the MyEnergi kit so that it will always wait for that amount of export before starting to take it.

Came here for battery drain and multiple CT clamps from different vendor equipment. Straightforward solution and well explained. Perhaps one day we'll have defined standards for Smart meters that extend power control into the home... for now it's KZfaq, Henley blocks and software hacks :o)

Excellent solution

Thank you Tom, very helpful, I'm about to get an EV and a Zappi and was trying to figure out a Solution using Solis config only...you can do it that way, but I think I'll go with your option right from install... 😊

Your solution was exactly the way my electrician put in my zappi. It works perfectly my 4k sola- Solis hybrid inverter and 10kw puredrive batteries run the house and my zappi will use any surplus from the sola and charge from the grid. You have done pretty much exactly the same as me and it works great. I just don't have an Eddi yet but hopefully soon. Thanks for the video it really helped me back up the decision to put in the Henry blocks. Ps: I get the same graph issues the data is pretty much correct but all the colours are wrong.

Good job man

Thanks for the excellent explanation, really clear. I am having the same problem with the battery draining during the day as soon as it drops below 100% and the Export Margin part does not apply. The Zappi then draws from my panels and batteries and does not stop. In addition at night, no matter what I do I cannot stop the battery discharging. Sadly I cannot see a way to limit the discharge of my battery through my Deye inverter while the car is charging at cheap times of the night. The firmware update has not solved the problem either. As a result, when I watched your video, I thought it would solve my problem, and it would......but it also nearly made me cry!!! When the installer first set up my zappi, it was put, in error, directly onto the mains and separate to the consumer unit. After many calls with them and myenergi, they came back, realised their error and wired it through the consumer unit. Of course, I now realise that leaving it alone would have solved my battery drain issue!

I had exactly the same problem, but solved it in a different way. My AC coupled system comprises of a 3.4kw grid tied solar system, a Sofar me3000sp inverter, Pylontech Us3000c batteries, plus a Zappi and an Eddi. After using 50w thresholds described in the My Energy forum, the flip flopping between components fighting for priority was cured but I still had the issue of the Eddi and the Zappi draining my batteries if either of them were set to use the Octopus Go 9.5p Tarriff between 12.30am and 4.30am. Switching off the batteries on nights I wished to charge the car was not a cost effective or convenient solution. I then discovered the time of use mode from KZfaq, especially the one posted by Rural Electric Systems on 1st May 2021. He was using old Sofar Firmware, version 3 hides the"Time Of Use Mode" under an extra "Work Mode Set" menu. He goes through setting manual override timers which are called "rules" . You can force the inverter to manually come out of auto mode and charge the batteries at given times. You can stack up these timers under rule 1, rule 2 etc. Each for various days of the week and months of the year, enabling them to work in conjunction with each other or alone. This functionality is not described in the manual. Other inverters probably have similar functionality, I don't know. Then the penny dropped, if the batteries are charging they can't be discharged! Initially I disregarded this thought as why charge batteries from the grid and potentially waste solar energy during the day? But Time Of Use mode let's you set the charge rate for each rule. I set the timer to switch on and off at Octopus Go times with the SOC (state of charge) set to 100% and a charge rate of only 100w from Jan 1st to Dec 31st. This works perfectly, 100w for 4hrs only costs arround 4p you could set it lower. The only downside is the house runs from the grid during those 4 hours, in my case the house only consumes about 200w at night, costing me arround 8p on the 9.5p Tarriff. I was then left with one unrelated issue that might be worth mentioning and could be limited to my type of Sofar inverter. Ben Allen in Poole who Carrie's out Pylontech repairs thankfully came to the rescue. My Sofar v3 firmware will only discharge the Pylontech batteries to 20% before switching back to the grid. He sent me a link to the setfirelabs.com website that explains in detail how to upgrade the Sofar me3000sp firmware to v3.06 with a link to the file download. This will enable discharge down to 10% for the Pylontech us3000c's which can cope with only 5%, so there is still a margine of safety. Hope this helps someone!

We have the same problem. We have 32 solar panels, generating almost 8kW at peak together with 17.7 kWh of battery storage. Looking at page 26 of the Zappi manual, it says that ... "If the property has a static AC battery system installed, it is possible to get the Zappi to work in harmony with the battery system, PROVIDED A CT HAS BEEN INSTALLED to monitor the battery inverter. Then in the Zappi settings, set it to "Avoid Drain' and this should stop the Zappi draining the battery when using surplus power from solar generation. So we are waiting to get another CT installed as described above and then we will see what happens.

Thanks for the video .I have the same setup as you ,but I use the battery to smooth out the solar output and keep my car charging , I just monitor the solar output and battery discharge so I can stop the Zappi charging and keep the charge I need in the battery.

Volume a bit low but nice video, got the exact same issue but I am already wired up like your new way, will try moving my CT clamp, thanks for tip

Nice video. I have the exact same experience. I have export set to 150w and it has been fine most of the time. I've the inverter set to self-consume and once the battery is fully charged, it allows then for the Zappi to run (due to observing export on the grid CT). Once the charge starts with say 2.5Kw of solar from the panels, 2.5Kw of that would be going straight to the car All is fine and works as I would expected. Battery is full at this stage with no discharge. The exact same thing happens that you explained: suddenly a cloud comes over and the solar generated drops, the inverter still thinks the house requires 2.5Kw, so then the inverter starts tapping into the battery to supply that demand. Even though I have export set to 150w, using my shelly EM I see it bounce around. It does try to get back to 150w export, but it is a sea-saw effect. Car charging is steady, but the odd thing is that if the sun is out again after a cloud passing, suddenly the charge is now heading to 3-4Kw. I'm just in this zone where the zappi observes a jump in export and adds that to the demand. I'm sure there is probably some adjustments to make with timings. For the meantime my fix is to set the battery on the solis app to not discharge during the day for a few hours if I have the car plugged in. A bit manual, but besides doing a rewire, it's the only way at the moment for me on a good sunny day to be sure. I may look at something smart with modbus and home assistant, but I suspect the rewire would be the faster approach.

Thank you, I have the same problem

Hi Tomas, thanks for a great video, I'm currently at the stage where I have the solar, Foxx inverter and home batteries plus an Eddie (with Harri), and using the Export Margin I have managed to balance my house battery drain when heating water. I have just got an EV so am now looking to get a Zappi installed, my hope is I'll be ok using the Export Margin tweak in v5 of the firmware to balance my car charging in the day from solar, the worry that I'm posting about is overnight charging of the EV. I want to be able to charge my car from the grid in my Octopus Go period (4 hours early morning), but I worry that this will start draining the batteries first. So as an example the car will start charging at lets say 3kw at 1am, my inverter will see this as house load and will start draining the batteries instead of letting the Zappi just take from the grid. I have heard that the way to overcome this is to set the house batteries to also charge at the same time, but in my scenario I don't want to charge the house batteries overnight, I want those to be topped up by the sun the next day. Could your rewire (which I could get done when having the Zappi installed) be a solution to this?

Thank you Tom for the video. If you set the Zappi to fast charge, will the battery discharge into the Zappi ?

Hi, where is the link to the original myenergi forum? I remember seeing it as it had little diagrams etc? Thanks L

Thanks Tomas - a really helpful video and nicely explained! I'm fairly new to all this, and just need a bit of help making sense of all these options! I have 4kW solar pv, an 8.2kW GivEnergy house battery, and a MyEnergi Zappi (v2) which I've just upgraded to v5. I'm a relatively low mileage, infrequent EV user and the house is new, all electric and pretty efficient (ASHP etc), though I don't find I'm exporting all that much overall. I'm thinking of getting onto the Octopus Intelligent tariff, so that I can charge the car at cheap rates overnight on those occasions I need to plug it in. And if the car battery is ever empty, I can usually afford to wait 3 nights to get back to a full charge. I've assumed that in winter, I could set the house battery to charge up from the grid during the off-peak hours (and if necessary set it to only discharge outside these hours), and then plug the car into the zappi on any evening I need some charge, set to add - say - 30% on any night between 2330 and 0530h. And in the summer, presumably set an export margin on the zappi, so I can keep the car plugged in during the day to capture any excess solar. Does all this make sense?! I don't think I need the Intelligent Flux tariff, as with my levels of use, I think any little I lose to the grid through low value export would be more than offset by the advantages of 7.5p/kWh off peak for house and car use. Many thanks, if you or others do have time to offer any comment/advice!

One of the issues your solar+battery setup has is that they share an inverter, which is great for efficiencies, but means that the Zappi has no idea of whether it's the solar panels providing the excess power (Zappi should consume) or the batteries (Zappi should NOT consume). That's the choice you have to accept with a hybrid solution (unless you can somehow monitor the DC power from the batteries to the inverter! ). Also your setup won't allow you to charge your car from banked solar when you come home at night. Of course if you only intend for the batteries to apply your house then this is moot. Great video!

Please tell me the sparky came back with more blanks for the new CU and tidied up the rough CT wiring 🙈

Did you try adding an extra CT clamp on the output of your inverter/battery so the Eddi and Zappy can monitor it? It will then show up in the myenergi app as a solar/battery device. That may have been a simpler solution than the re-wire. I have the same setup and use two of the wireless harvi CT clamps. One at the smart meter and one at the inverter/battery output.

Im looking at a huawei solution for inverter and batteries and with launch of new huawei 7kw charger am i better off to wait to gain from better potential integrations than using seperate manufacturers and trying to come up with workarounds.

Tomas great video. Would this be an issue with a three phase zappi? I am guessing it would?

Hi, great explanation of the issue! I have a similar set up: 7kw solar, 5kw solar edge inverter, zappi, eddi and a tesla powerwall 2. I initially had the same issue, but the export limit and setting priority order for surplus solar to: house, eddi, battery, zappi completely solved the issue. The only remaining issue is the frequent stop starting of solar surplus to the car due to british weather. I worry as to what impact this constant charge cycling will have on car battery life and also the wear and tear of constantly stop/starting may have. I intend to solve this by going on to Octopus Flux tariff and charging my car and tesla powerwall only in the 3 hour night window; letting amost other surplus solar go to export. At 20p for export and 18p for import during the night window, this makes financial sense and means my car has a nice, level, regular charge of about 21kwh per night which will cover my 250 mile per week use (car averages 3.1 miles per kwh so needs 70 kwh per week of charge). Hopefully my solution makes sense? I might also flip to octopus go for a few months in winter when solar production crashes and back timo flux in March.

Can I ask and apologies if I missed is your battery DC? I am sure my inverter and battery on a different CU what difference if any would this make? I am even happy to have all battery and solar excluded from Zappi as it is a small array. Last still works the same boost charging?

So my tails go into a Henley block in the meter cabinet and the zappi is taking power from there into a separate consumer unit for the zappi. I’m having solar and battery next month and wonder if this will prevent my zappi from discharging my battery

I solved this by writing some software off a Raspberry PI that controls the Zappi, my Tesla M3 and sets the Zappi to Eco mode to only charge when the Tesla Powerwall reaches 98% and stops charging when it gets to 95%. This deals with any fluctuation in use/generation and ensures that the Powerwall is at least at 95% at the end of the solar day. I can then run it in a different mode that sets the Zappi to 7kw between 11:30 and 5:30 (Octopus cheap tariff) and the Powerwall is set to not discharge during these hours. The Raspberry PI is then controlled using a 'front-end' UI off my phone (the RP is programmed using NodeRED). I was doing all of this manually for a long time but decided to set it up this way so that is was easy for the wife to use. It also ensures that I don't export at all during the year (as long as I keep space in the M3 for charging).

I have a zappi and 2 solar inverters and a battery with inverter. I'm experiencing battery drain when octopus intelligent gives me non standard mid afternoon charging slots . I can fix by manually setting new battery charge times but want a better solution. Any ideas

Yeah I’ve just finished commissioning my Victron system I’ve designed it with a Hager split board so just moved the EV circuit grid side and moved the CT for the Victron after the EV circuit and then the EV CT to the grid so it can load balance and grad the solar before the grid gets it after the batteries have charged. Hardwire over software everyday! Ever want a different charger your in the same boat design the system to incorporate all or most scenarios, rather than relying solely on software.

That sounds about the same situation I was experiencing, however, I did notice you were charging the car at 3.5kwh but surely the Zappy can deliver 7kwh, why?

Could you not have used Harvi with 1 ct on main and 1 ct on inverter?

I've had this issue as well, the best solution depends on what you want to achieve. If your main aim is to use as much of your solar electricity without exporting then I don't think you need to do this. If you have your Zappi set on eco+ and the batteries set to only discharge during. the day it shouldn't drain the battery but only export excess. In the evening your batteries power your house and then your car can charge at night draining the battery if you want?

Hi Tom, great video, you have come to my rescue after being a bit unconvinced by the myenegi solutions. Had my install for a month and have been having the same issues. Does the solution cause any issues with night time scheduled grid charging of either the EV through the Zappi or home batteries through the inverter. Will it restrict any of the charging capacity through the zappi or inverter. New to all this and still in communication with the instllers so hopefully they will sort. Cheers Craig

So you are constantly drawing from the grid for your Zappi, when random cloud cover etc, to charge up your car at a slower rate. You don't want a 100% renewable energy strategy? Wouldn't it be better to get an additional battery and then use more renewable with a faster charge rate?

High Thomas.. sorry Fella but you are to guiet….see how Rosie Barns comes over in you tube, here’s hoping we will see you again with better audio…..Brian

Solax Batteries, when charging the car overnight on GO reduce Solax battery charge to less than 50% if you do not need a battery charge, good for summer in winter battery system charged to 100% works for me as I do have solax master and slave 11.6kwh charge times same for EV on Go Off Peak.