MG4 + Zappi Charger + Solar = a problem

[STG]

This is all very interesting. I am using my Zappi for the first time as I type. My main question is whether the Zappi will allow the car to balance when it gets to 100%, or whether it will see 100% in the car and just cut off the power. It's no big deal to switch to the granny lead to let the car balance I suppose, but it would be nice not to have to.

It will balance.

Yesterday I got home late and realised the car needed a little bit extra to cover this morning's driving. I didn't go near the Zappi, just plugged in the granny lead. That took power from the home battery, which could stand it, and I stopped the charge after a couple of hours, at 1.30 am, with the battery still looking reasonable.

The granny lead will take power from the battery like any other 13a device (TV,Freezer etc) and when the battery depletes it will then take from the grid (if the sun is not shining) where as the Zappi if put on FAST charge or a scheduled ECO++ charge then it will take from the grid. I have my ECO++ scheduled for 2-5am (Cheap rate on Octopus Flux) the rest of the time it's sun powered.

When I woke up at 8.15 the battery was down at 18%, having powered the house all night, but the sun was beginning to do stuff, certainly enough to keep the house ticking over. I decided the car needed a little more and started the granny charge again. When the battery got down to 5% it stopped discharging and switched the load to the grid, so I stopped the charge as I had enough. Battery probably trying to protect itself.

Yes, it cuts off before full delpeation. I have mine set at 10% to cut off.
How big is your house battery? ie in kW, for example I have dual 9.4kW batteries making 18.8kW potential.

About then the sun began to break through and I went off for a music lesson. I watched what was going on during the 2-hour lesson, until I was told off for inattentiveness! One thing that confused me, and I see it confirmed in the GivEnergy web page, is that even when the battery was still under 50%, it would chuck power to the grid if the solar was fairly high. To me this is a waste as I'm not yet getting paid for export (G99 not yet come through), and even if I was, isn't it better to hold on to it than to sent it away? Maybe the battery has a maximum charge power less than the solar can generate? But we're only talking 6.6 kw from the solar, I'd have thought it could handle that.

My G99 only took over a week to come back, then it's just giving your electrical supplier the MPAN number. With Octopus you do this online and I was being paid for export 3 days later (as long as you have a SMETS2 electric meter or a compatible SMETS1 meter. Mine is a compatible SMETS1 so it worked straight away. Basically if your meter can send reading every 30mins then your OK

I got home on 7% charge in the car, because I'm still trying to do this <10% to 100% charge that I aborted last week. About half an hour later the home battery got to 100% and I decided the car wanted the sunbeams now. I started with the granny lead but soon realised that was taking only a small fraction of the solar output, leaving a lot to go back to the grid, so switched to the Zappi. This had the opposite issue, in that the system now needed some grid power to keep up the full charge speed. (I didn't use one of the eco modes because I want that charge to happen in one uninterrupted exercise.)

Correct.

At first the system seemed to want to protect the battery, keeping it at 100% by taking power from the grid. But after a while the battery started to kick in as the solar generation faded, and it's now down to 50%. It'll probably have discharged by the time the charge finishes at 9.20. I don't really mind, I'm using up a little bit of the credit I still have with Scottish Power in advance of the switchover to Octopus tomorrow, but I'm trying to understand the logic of what's happening.

I don't yet have a variable tariff (by the end of the week I hope) or an export tariff (maybe as long as July, I'm told), so there will be these things to get to grips with. Also the installer said to leave the car plugged in to the Zappi on eco mode and it would just take what excess solar happened along, so I might try that tomorrow (although I'll have to go on a joyride first to get the car battery down a bit!)

All very interesting, and complicated by me trying to do that long charge, but I'm learning. I hope to get to a place where I can just leave it all set up in a favourable configuration and let it get on with it with miminal interference, but I need to understand the logic of how it works first!

It will come to you quickly, and I bet you will be looking at the stats all the time seeing how much is being generated. I still look several times a day.

If you want to take advantage of your energy suppliers cheap import rate, then schedule high energy things for that time, I set the dishwasher and washing machine to operate during 2-5am, this way you make sure you don't use during the day especially on cloud days and end up using the grid as there is not enough house battery to supply the couple of kW's they use and if this happens during the evening it could cost you a lot as for example Octopus Flux 4-7pm it costs 33p/kW. Better to use it at 2-5 for 14p/kW


I also have a scheduled 3 hour Zappi ECO++ for 2-5am, so if the car happens to be plugged in then it gets charged at a cheap rate, I can manage 21kW MG charging during that 3 hour period and it only costs me £3 to give the car a 30% charge. That's the only time I use a scheduld Zappi charge and the inverter is capable of charing the car at 7kW and also topping the house batteries and provide house consumption.

My Luxpower inverter has a weather system built in which also controls the battery charging depending on the next day's weather conditions, it sets the SOC between 50% to 90% to charge to during the 2-5am period.

 

[johnb80]

Normal charging works fine, I will double check my firmware is uptodate but I usually get alerts on the app for that and have not seen anything recently.

But if you stop the charger and then try to start it again without unplugging does the charge restart?

The way the solar is integrated revolves around the CT (Current Transformer) and the pilot signal.

With a car plugged in ready to charge and the ZAPPI in Eco+ mode, the ZAPPI will monitor the CT looking for export of power. When the export rises to 1.4 kW it will modulate the pilot signal, it changes the PWM value to inform the car it can now draw 1.4kW via the charger. If the house load decrease or there is more solar available, it will again modify the PWM signal to tell the car it can consume more. Conversely if a cloud obstructs the sun or it goes dark, the PWM will change until it reaches 1.4 kW, at this point any further reduction would result in ZAPPI stopping and waiting for surplus. The car will know due to the PWM going to stop. The system on the car should be able to tell that it hasn't been unplugged (due to resistors and voltages on the pilot line being sensed). Charging from solar in this way is very little different to charging from the grid supply, it just has the ability to increase of decrease charge output.

 

[Rolfe]

It will balance.


The granny lead will take power from the battery like any other 13a device (TV,Freezer etc) and when the battery depletes it will then take from the grid (if the sun is not shining) where as the Zappi if put on FAST charge or a scheduled ECO++ charge then it will take from the grid. I have my ECO++ scheduled for 2-5am (Cheap rate on Octopus Flux) the rest of the time it's sun powered.


Yes, it cuts off before full delpeation. I have mine set at 10% to cut off.
How big is your house battery? ie in kW, for example I have dual 9.4kW batteries making 18.8kW potential.


My G99 only took over a week to come back, then it's just giving your electrical supplier the MPAN number. With Octopus you do this online and I was being paid for export 3 days later (as long as you have a SMETS2 electric meter or a compatible SMETS1 meter. Mine is a compatible SMETS1 so it worked straight away. Basically if your meter can send reading every 30mins then your OK


Correct.

It will come to you quickly, and I bet you will be looking at the stats all the time seeing how much is being generated. I still look several times a day.

If you want to take advantage of your energy suppliers cheap import rate, then schedule high energy things for that time, I set the dishwasher and washing machine to operate during 2-5am, this way you make sure you don't use during the day especially on cloud days and end up using the grid as there is not enough house battery to supply the couple of kW's they use and if this happens during the evening it could cost you a lot as for example Octopus Flux 4-7pm it costs 33p/kW. Better to use it at 2-5 for 14p/kW


I also have a scheduled 3 hour Zappi ECO++ for 2-5am, so if the car happens to be plugged in then it gets charged at a cheap rate, I can manage 21kW MG charging during that 3 hour period and it only costs me £3 to give the car a 30% charge. That's the only time I use a scheduld Zappi charge and the inverter is capable of charing the car at 7kW and also topping the house batteries and provide house consumption.

My Luxpower inverter has a weather system built in which also controls the battery charging depending on the next day's weather conditions, it sets the SOC between 50% to 90% to charge to during the 2-5am period.

Indeed, it's balancing now. It's beginning to get dark and the PVs are managing a whopping 13 watts. The grid import has dramatically dropped, obviously. The battery (which is 9.5 kwh) has been doing some slightly weird things, It dropped to 5% just before seven and I thought, that's it, it will just stay down there until the sun comes up again tomorrow. But no, it suddenly came back up to 8% and then 9% and went on contributing a small amount, a couple of times putting in a spurt that caused the grid import to back off a bit. It's still trickling in 97 watts to the mix although it's showing 6%. No idea what is motivating it.

I think I managed to get the bulk of the sunshine that happened today into the car, either directly, in the afternoon, or indirectly from the battery which charged up on the morning sunshine. Still imported almost 33 kwh, but as I said I'm just using up some credit before I leave my old supplier, and it's all good learning. And the long charge has been done, uninterrupted this time.

My smart meter seems to be OK, but for some reason Scottish Power is playing hardball with my installer about the G99. He's not sure why but thinks it might be because of next door, where he installed the same system last year. He quoted the length of time they have to respond, something like 40 working days which takes us to the middle of July, but he said he'd keep badgering them. The slightly annoying thing is that I'm going away next week for a week, and since the house will be consuming very little and the car will be elsewhere, there's likely to be a lot of unpaid export. Well, at least the system is in - I could still be waiting for an install!

I don't have a cheap-rate tariff as yet but I was thinking of the one that gets you six hours at 7.5p. That way I could charge the car, fill the battery (on sunless days) and run the dishwasher and the washing machine, all at that price. And the battery should then ensure that the rest of the day's usage is also at that price, though I'll have to get a feel for how much I use while cooking. I should be able to switch over to a variable tariff within the next few days, although I won't really be making use of it till I get back.

Thanks everyone for your useful contributions.

 

[jeegnesh]

I don't have a cheap-rate tariff as yet but I was thinking of the one that gets you six hours at 7.5p. That way I could charge the car, fill the battery (on sunless days) and run the dishwasher and the washing machine, all at that price. And the battery should then ensure that the rest of the day's usage is also at that price, though I'll have to get a feel for how much I use while cooking. I should be able to switch over to a variable tariff within the next few days, although I won't really be making use of it till I get back.

I use the 7.5p tariff, over the winter I also use that to charge the batteries and then use that thru the day, in the summer or now I only top up the battery for a short period like an hour or so.

to get onto that tariff you have to have a compatible car or charger, and in your case the car is not but the Zappi is and when you do this myenergi basically takeover your Zappi - so for charging you go into the Octopus app and you get a new tab called devices where you select what % top up charge you want in increments of 10% and by what time, then whenever you plugin Ocotpus creates you a charging schedule to accommodate.

Your fast and Eco settings are basically disabled, if you set them it will jump back to eco+ within a minute or so, if you want a popup boost you have to go into the Octopus app and there is a boost you can fire.

It all seems mad at first but after a while you figure out who it all works and its actually fine, I had control issues initially

But if you stop the charger and then try to start it again without unplugging does the charge restart?

The way the solar is integrated revolves around the CT (Current Transformer) and the pilot signal.

With a car plugged in ready to charge and the ZAPPI in Eco+ mode, the ZAPPI will monitor the CT looking for export of power. When the export rises to 1.4 kW it will modulate the pilot signal, it changes the PWM value to inform the car it can now draw 1.4kW via the charger. If the house load decrease or there is more solar available, it will again modify the PWM signal to tell the car it can consume more. Conversely if a cloud obstructs the sun or it goes dark, the PWM will change until it reaches 1.4 kW, at this point any further reduction would result in ZAPPI stopping and waiting for surplus. The car will know due to the PWM going to stop. The system on the car should be able to tell that it hasn't been unplugged (due to resistors and voltages on the pilot line being sensed). Charging from solar in this way is very little different to charging from the grid supply, it just has the ability to increase of decrease charge output.

yes it charges if I unplug and plug.

the problem is some cars have a max charge on/charge off for a day or a time period and then think something is wrong and report full to block the charge, it turns out this is a known issue and myenergi say this is a problem on the EV side, here the workaround they suggest for cars that do this:-

https://support.myenergi.com/hc/en-gb/articles/360019305197-Charge-Delayed#01HKAMDXZDX1Y3D55ARFVB2S08

This worked perfectly yesterday, only time will now tell if it continues that way.

 

[Rolfe]

Thanks for all that! First I have to get the tariff though...

 

[johnb80]

I use the 7.5p tariff, over the winter I also use that to charge the batteries and then use that thru the day, in the summer or now I only top up the battery for a short period like an hour or so.

You can make better use of Octopus tariffs by exporting all what you generate (15p kWh) and charging your batteries off peak (7.5p kWh). You can also discharge spare battery capacity during the evenings before 23:30

to get onto that tariff you have to have a compatible car or charger, and in your case the car is not but the Zappi is and when you do this myenergi basically takeover your Zappi.

I would suggest Octopus are in control via the API.

so for charging you go into the Octopus app and you get a new tab called devices where you select what % top up charge you want in increments of 10% and by what time, then whenever you plugin Ocotpus creates you a charging schedule to accommodate.

Increments are 5% and Octopus doesn't guarantee to make the schedule to accommodate, they will try though, often extending the schedule into peak times but only charge off peak rates.

Your fast and Eco settings are basically disabled, if you set them it will jump back to eco+ within a minute or so,

Well not really disabled. The Octopus system sees you are charging (mode irrelevant) and then issues a schedule to selecting ECO+ as well. Simply switch off smart charging in the app and all modes will work as they did prior to Octopus Go Intelligent.

if you want a popup boost you have to go into the Octopus app and there is a boost you can fire.

In many cases, just plugging in with appropriate times set, Octopus will give you a schedule during peak times at off peak rates. Sunday morning every week we charge at 06:00, we usually get a schedule up to 11:00 which covers the washing and tumble drying very well.

It all seems mad at first but after a while you figure out who it all works and its actually fine, I had control issues initially

Understanding this complex task can at first be daunting but reality is its easy to use, very flexible and the best priced charging tariff on the net.

yes it charges if I unplug and plug.

the problem is some cars have a max charge on/charge off for a day or a time period and then think something is wrong and report full to block the charge, it turns out this is a known issue and myenergi say this is a problem on the EV side, here the workaround they suggest for cars that do this:-

https://support.myenergi.com/hc/en-gb/articles/360019305197-Charge-Delayed#01HKAMDXZDX1Y3D55ARFVB2S08

This worked perfectly yesterday, only time will now tell if it continues that way.

The only problem with this solution is it doesn't stop the charge when it really should due to the delay. MyEnergi suggest 240 seconds for the stop delay. If your export disappears your Zappi will continue charging for 6 minutes importing upto its 7kW rate from the grid thereby using .7 kWh at full price peak rate. It's all down to really poor car design, the manufacturers need to do an update to resolve it.

 

[jeegnesh]

You can make better use of Octopus tariffs by exporting all what you generate (15p kWh) and charging your batteries off peak (7.5p kWh). You can also discharge spare battery capacity during the evenings before 23:30

Not applicable to me the government FIT scheme I am on pays for everything generated used or not and at a higher rate than 15p, but only solar generation counts, I don't believe I can then also join the outgoing scheme.

In many cases, just plugging in with appropriate times set, Octopus will give you a schedule during peak times at off peak rates. Sunday morning every week we charge at 06:00, we usually get a schedule up to 11:00 which covers the washing and tumble drying very well.

Now this interests me, currently I always set the charge to be ready by 5:30am thinking after that it would charge more, are you saying if I set the charge by time to say 9am, then the schedule may include times outside of the 11:30-5:30 and the 7.5 rate would apply to all usage so I could use more stuff during my awake time?

The only problem with this solution is it doesn't stop the charge when it really should due to the delay. MyEnergi suggest 240 seconds for the stop delay. If your export disappears your Zappi will continue charging for 6 minutes importing upto its 7kW rate from the grid thereby using .7 kWh at full price peak rate. It's all down to really poor car design, the manufacturers need to do an update to resolve it.

Not ideal I agree, but I'd rather take the hit than losing my solar charging altogether by the forced false full message

 

[johnb80]

Not applicable to me the government FIT scheme I am on pays for everything generated used or not and at a higher rate than 15p, but only solar generation counts, I don't believe I can then also join the outgoing scheme.

Yep if youre on FIT then that's good but for newcomers they wont be on FIT and therefore what I said applies (just to be clear to the audience )

Now this interests me, currently I always set the charge to be ready by 5:30am thinking after that it would charge more, are you saying if I set the charge by time to say 9am, then the schedule may include times outside of the 11:30-5:30 and the 7.5 rate would apply to all usage so I could use more stuff during my awake time?

Yes it may do, or, do as I do, I set our MG charging on Sunday mornings anywhere between 5:30 and 6::00 asking for it to be ready by 11:00. Every Sunday it obliges and we have off peak from 23:30 through to 11:00 the next day. Some people will say this is 'gaming the system' but so far it's worked for me and Octopus are non too fussed about it when I've asked.
I usually import 50+ kWh on Sunday morning.

Not ideal I agree, but I'd rather take the hit than losing my solar charging altogether by the forced false full message

Yep, it needs sorting by the car manufacturer.

 

[Rolfe]

I suppose I can come back and read this again when it makes more sense to me. I still haven't managed to move over to Intelligent Octopus Go, they're still saying "we're still getting your meter data". Despite that I gave them a reading this morning as requested, and they have that on record. Sigh.

Today was the first day of the New World of Solar, I don't count yesterday because I was still on Scottish Power and charged the car to full on their dime. So I have a car at 100% now, and I'm heading for points south on Tuesday. I'm not sure how best to play getting the car back up to 100% for that, given that I'll use a bit tomorrow evening at least.

 

[DevonMG4]

Is anyone else having this issue with Zappi or solar excess charging?

In answer to your question, yes. MG4 all through 2023, Zappi V2.

If it's a blue sky day I have left it plugged in, if there are lots of fluffy cumulus to occasionally stop the charge I keep it unplugged.

Came to the conclusion last summer that the car will tolerate so many stop starts and then declares enough is enough and I'm not playing any more and stops the charge.

If surplus is likely to dip to about 1 kW with cloud cover then I have set the green slider to 70% and extended the timeouts you have found on the basis that 70% will result in an equivalent cost of my off peak tariff, so quite acceptable till the cloud moves on and we are again charging at 2-3 kW.

But yes our MG4 does not tolerate too many charging interruptions.

All a bit academic now as I have no desire to charge off solar, at 15p/kWh export and 7.5p import off peak, there is no point in self consuming.

I've not looked at the info in #24 as yet.

 

[FiferMG4]

Hiya

Got my MG4 on Monday and really enjoying so far, few pain points but learning.

Current biggest concern is the charging, I had a leaf with the exact same setup and that worked as it should, but now with the MG4 in the picture having a problem.

Basically my Zappi charger is set to Eco++ which means when my solar is in excess by 1.4kW the charger will fire and car will charge. This kicks off fine, on days with cloud cover etc anytime it drops below 1.4kW the charge stops and then should restart when above 1.4kW. What I have noticed is that when this happens the MG4 on the stop charge is report the battery is full and so it will not accept further charge -- which is totally wrong the car is at 44%.

If I unplug and plug the charger then it will kick off on excess and then at some later point when it has maybe stopped and started it again says the car is full, so no further restarts.

Is anyone else having this issue with Zappi or solar excess charging?

Hello Jeegnesh,

I’ve had a Zappi, solar panels, a home battery and MG4 for just over a year and I don’t think I’ve ever used the eco++ mode. I always set the Zappi to eco+ mode when there’s a decent amount of sunshine. When the inevitable cloud makes its way over the house, the battery makes up the difference. I sometimes play with the GivEnergy battery discharge settings, so that the car doesn’t drain the home battery in a few short hours, say 800 watts on a sunny day. Just enough so that the grid doesn’t come into play.

During December and January I had to resort to the fast charging mode on the Zappi and set the home battery discharge rate to its minimum. Of course, the limited amount of solar during those months went into the car. Got a big fat 190 watts on the 27th of December. ? I can’t (don’t more like) remember, but that must have been a very dull day.

 

[jeegnesh]

Hello Jeegnesh,

I’ve had a Zappi, solar panels, a home battery and MG4 for just over a year and I don’t think I’ve ever used the eco++ mode. I always set the Zappi to eco+ mode when there’s a decent amount of sunshine. When the inevitable cloud makes its way over the house, the battery makes up the difference. I sometimes play with the GivEnergy battery discharge settings, so that the car doesn’t drain the home battery in a few short hours, say 800 watts on a sunny day. Just enough so that the grid doesn’t come into play.

During December and January I had to resort to the fast charging mode on the Zappi and set the home battery discharge rate to its minimum. Of course, the limited amount of solar during those months went into the car. Got a big fat 190 watts on the 27th of December. ? I can’t (don’t more like) remember, but that must have been a very dull day.

Because I'm on the Octopis Intelli Go tariff it will not allow me to use eco setting, is part of the rules of being on the tariff, if I switch to eco, octopus very quickly reverts it back to eco+

 

[johnb80]

Because I'm on the Octopis Intelli Go tariff it will not allow me to use eco setting, is part of the rules of being on the tariff, if I switch to eco, octopus very quickly reverts it back to eco+

You simply switch off the smart charging in the app, use whatever mode you want then.

 

[jeegnesh]

You simply switch off the smart charging in the app, use whatever mode you want then.

I hear a rumour they do not like you doing that too often, it almost suppose to be a debug testing mode, may be wrong.

So on Friday extending that timeout helped and charging on surplus solar worked well.

Yesterday and today after returning from a drive and plugging in while airplanes was available it came up with charge blocked - EV blocking charge.

By change I decided to take off my after market type 2 cable and use the one supplied by MG and it started charging straight away on the surplus.

Was this just luck are all type 2 cables not made equal? The nonMG cable never caused the Leaf to have a problem for reference.

 

[johnb80]

I hear a rumour they do not like you doing that too often, it almost suppose to be a debug testing mode, may be wrong.

Wherever you heard it from is duff information, I have discussed this with Octopus directly and there isnt an issue at all. The T&C's state at least one charge per month should be done under their control but thats all. I know of people that have switched off smart charging for months without issue.

 

[jeegnesh]

Wherever you heard it from is duff information, I have discussed this with Octopus directly and there isnt an issue at all. The T&C's state at least one charge per month should be done under their control but thats all. I know of people that have switched off smart charging for months without issue.

 

[johnb80]

View attachment 26683View attachment 26683

I'm not sure what your point is?

This is in the app, it only suggests you leave it on to get cheaper prices at any time of day. Octopus put the switch there to be used, it's not an issue.

 

[jeegnesh]

If you see my pic the suspend is supposed to be used whilst trying to debug an issue not as a switch for you to turn on and off as you desire.

The thing is I know most likely they will not boot you off the tariff but it does provide them a reason if they so wished sometime in the future.

I recall a discussion I had with customer services after connecting to Go asking if I could suspend or disconnect to which they said if you do you may be removed from that tariff, but clearly they do not seem to enforce this.

 

[johnb80]

If you see my pic the suspend is supposed to be used whilst trying to debug an issue not as a switch for you to turn on and off as you desire.

Yet in my picture clearly it is a switch there to be used with the statement leave it on to get smart charging out super low rates.

In your picture it's suggesting that you can suspend rather than disconnect if theres an issue. It doesn't suggest that suspending smart charging will remove you from the tariff.

I recall a discussion I had with customer services after connecting to Go asking if I could suspend or disconnect to which they said if you do you may be removed from that tariff, but clearly they do not seem to enforce this.

What does this suggest to you? Maybe they were saying you could be removed from the tariff if you disconnected your device and of course that is the case, why wouldn't it be? Clearly there's an option in the app not to use the smart aspects, why would they want to suspend you when the option is to supply peak rate electricity at off peak prices? theyre winning here.

 

[tsedge]

My take on this is that the whole thing is an experiment to learn how people use it and as such there's no enforcement at the moment, they seem quite relaxed. I leave mine permanently on +80% even though I rarely need to charge that much.

This might change in the future or might not, we'll see.

It does seem to me that not being able to read the car's SOC is a big handicap for Octopus, but on the other hand they are dealing with large numbers of people, so it may be that statistically this all evens out and they are pretty happy regardless of a few people turning it on and off again.