MG4 Granny Charge versus Public Charge Until Wallbox Installed

[FrancisM]

We got both leads with our trophy last week ( he said there were a few type 2 spare and saved one for us). I tried a charger the first night on a socket in the garage and short extension lead I think I'm either going to get an outdoor socket wired or ohme charger so we can get intelligent go. Are there any other chargers that support octopus?

Do you want tethered or untethered?

I'm doing my first charge now with an EVDance portable/granny charger (off eBay as used, but I can't see any signs of use). I can adjust the current with this, although I now realise the car has a setting for that too. The charger defaults to 13A so am trying that whilst checking the plug temp regularly. Charger says charging at 12A, 2.85Kw. iSmart App says 2.7Kw. I've used iSmart to set health mode to 70% charge.

If the plug gets too hot, I'll stop charging and adjust the charger to 10A then restart etc.

EDIT: I've revised the health mode to 60% to check it will obey the setting sooner.

Well. the car stopped charging the battery when SoC reached 60%. Good. But the port LEDs were still green and the granny charger still thought it was charging at 0.1A, 0.24Kw. So I guess a trickle was going in to the car to feed the electronics. I had to stop the charging in iSmart, then the charger stopped. I have now set it going again with a health mode of 70%.

One of the port LED bars is unlit. Is that a SoC display?

 

[Rolfe]

Well. the car stopped charging the battery when SoC reached 60%. Good. But the port LEDs were still green and the granny charger still thought it was charging at 0.1A, 0.24Kw. So I guess a trickle was going in to the car to feed the electronics. I had to stop the charging in iSmart, then the charger stopped. I have now set it going again with a health mode of 70%.

One of the port LED bars is unlit. Is that a SoC display?

Your car was doing a balance charge. Best to leave it alone till it's finished. You know it's finished when the charging power and finish time are simply blank, rather than showing a small amount of power (or 0.0 kw) and the current time. And the app changes to read "not charging".

 

[FrancisM]

Your car was doing a balance charge. Best to leave it alone till it's finished. You know it's finished when the charging power and finish time are simply blank, rather than showing a small amount of power (or 0.0 kw) and the current time. And the app changes to read "not charging".

Surely balancing only occurs at close to fully charged, so no balancing at 60%?

The app was saying "not charging", I think. I'll check again when it reaches the 70% limit I have set.

 

[Rolfe]

The NMC battery will balance to some extent at lower states of charge, although it is best to let it balance at 100% once a month or so.

 

[davidfarmilo]

That's the way to go.. ohme are cheaper but I recommend the myenergi zappi, British made with good support, also best for solar integration in my opinion, the display is excellent so you can see what's happening.

We don't have any solar and I suspect aren't very likely to get any

 

[FrancisM]

Surely balancing only occurs at close to fully charged, so no balancing at 60%?

The app was saying "not charging", I think. I'll check again when it reaches the 70% limit I have set.

I waited for around half an hour

The NMC battery will balance to some extent at lower states of charge, although it is best to let it balance at 100% once a month or so.

Well, I waited for about half an hour when it reached 70% until the status went to "not charging", so it looks like you are right.

 

[Rolfe]

My SR works differently, but this is what I have heard about the NMC. I think the time taken to balance can be quite variable, especially for the NMC, but half an hour seems to be about par for the course.

 

[HazardLights]

I doubt that your RCD is 30 amp, you probably mean 30mA which is the fault tripping current. Have another look and it should have a current rating on it too, usually 40A, 63A or some such figure. Also is the garage socket on a circuit which has an MCB fuse protecting it? this also will have the current rating, usually 16A, 20A or 32A. you can check by switching off each circuit and seeing if a lamp plugged into the socket goes out.
Probably nothing to worry about but best to make sure what is the electrical protection on the socket. There is a 13A fuse in the plug so that will almost certainly be less than the circuit protection.
Theres nothing wrong with granny lead charging (also called mode 2, as distinct from type 2 connector). Wall box is mode 3. Just dont use an extension lead unless its an emergency, more resistance and more to go wrong! Hope this helps, I am a (semi) retired electrician.


If youre going to use an outside socket regularly to charge I would recommend replacing it with the Masterplug EV socket, sold by Halfords online, about £50. Not a lot of difference (quite a bit bigger and with an integrated RCD) but maybe worth it for peace of mind. Oh and the socket is switchless - the switch is often the weak point on a socket in my experience due to the small contact area.

Thank you for your great advice. I think these pictures should give you the information you need. I assume I should get an electrician to replace the socket rather than doing it myself (I have no qualifications in this area beyond tinkering with tech). It's amazing how dirty the garage stuff is once I actually look at it! The distribution board was upgraded recently after a number of electricians struggled to believe the previous owner was an electrician and had done the work. The bottom picture of the garage is unchanged from previous owner. There is a light powered off it too. I may change that to LED as it is old although only gets brief use so not a big deal.

 

[HazardLights]

We got both leads with our trophy last week ( he said there were a few type 2 spare and saved one for us). I tried a charger the first night on a socket in the garage and short extension lead I think I'm either going to get an outdoor socket wired or ohme charger so we can get intelligent go. Are there any other chargers that support octopus?

Select your EV charger

The UK's most awarded energy supplier. We're doing energy better - for you and the environment.

octopus.energy

 

[HazardLights]

To update on what happened once I got an MG4. As the battery was about half full and I am off to Bridge of Allan tomorrow I have taken the opportunity to do a battery friendly trickle charge to 70%. I am at 65% now and the socket and plug have no perceptible warmth. Which surprised me as I thought I felt a little warmth at the very beginning.

 

[salty]

To update on what happened once I got an MG4. As the battery was about half full and I am off to Bridge of Allan tomorrow I have taken the opportunity to do a battery friendly trickle charge to 70%. I am at 65% now and the socket and plug have no perceptible warmth. Which surprised me as I thought I felt a little warmth at the very beginning.

Probably felt warm, because you was expecting it to feel warm, after all what you have read. I was the same, but it never even got warm, I've granny charged it a few times now. ??

 

[Rolfe]

Might just be that the air temperature fell between feeling it at the beginning and later on.

 

[HazardLights]

Might just be that the air temperature fell between feeling it at the beginning and later on.

It certainly did. It's a decidedly chilly 7°C now and will get down to 4C tonight. I realise single digit daytime temperatures are coming but it's amazing how quickly we have swung from decidedly warm to this.

I am off to Halfords as the MG granny charger is short and had to hang from the socket which I seem to remember induces stress in electricals. I saw a highly rated extension cable in Halfords when I was last in and that should do the job. I think granny charging will bridge me over until the end of the month when I get my charger. I am tempted to get the socket changed to an EV socket and perhaps moved to the outside of the garage wall so I can close the garage door even though I cannot see a long term use for it.

@Rolfe (or anyone) did you mention in a post somewhere that balancing on an Ohme challenger may be doubtful or was that just a weird dream that I had?

 

[FrancisM]

At 12A charging, my plug was slightly warm but the warmth didn't build even after 2 hours. Might limit it to 10A for a long charge . The MG charger might limit current to 10A but that's not what I have.

 

[HazardLights]

At 12A charging, my plug was slightly warm but the warmth didn't build even after 2 hours. Might limit it to 10A for a long charge . The MG charger might limit current to 10A but that's not what I have.

It does

 

[LenEV2016]

It certainly did. It's a decidedly chilly 7C now and will get down to 4C tonight. I realise single digit daytime temperatures are coming but it's amazing how quickly we have swung from decidedly warm to this.

I am off to Halfords as the MG granny charger is short and had to hang from the socket which I seem to remember induces stress in electricians. I saw a highly rated extension cable in Halfords when I was last in and that should do the job. I think granny charging will bridge me over until the end of the month when I get my charger. I am tempted to get the socket changed to an EV socket and perhaps moved to the outside of the garage wall so I can close the garage door even though I cannot see a long term use for it.

@Rolfe (or anyone) did you mention in a post somewhere that balancing on an Ohme challenger may be doubtful or was that just a weird dream that I had?

Remember and uncoil all your extension cable if on a reel.

Ohme chargers are great but because I have it linked to my IO tariff I personally think it just stops at 100% just about bang on when I set it to charge to that (I don't have an LFP battery)
I then about once a month after doing that just bung it on the granny in the morning and it normally shows it's charging for about 10 minutes before stopping

 

[HazardLights]

Remember and uncoil all your extension cable if on a reel.

Ohme chargers are great but because I have it linked to my IO tariff I personally think it just stops at 100% just about bang on when I set it to charge to that (I don't have an LFP battery)
I then about once a month after doing that just bung it on the granny in the morning and it normally shows it's charging for about 10 minutes before stopping

I will do. I also noticed that there is one of those "hang me on a nail" things on the back of the granny charger. I will look later but I may just have a wooden stud in reach. Sadly, due to dumb mode meter I cannot access any lovely overnight tariffs but if they introduce 4G meter upgrades I will jump at the chance.

 

[Rolfe]

I know nothing about Ohme chargers! It just so happened that I had installed a plastic shelf unit in the garage right where the socket that I use for the granny charger is, so it sits neatly on that. My electrician said it was fine and particularly pointed to the cool dark position as a reason not to expect any trouble. He said that in cool conditions any heat would dissipate, but that if the socket was in full sun it might be a different matter.

 

[FrancisM]

Had my Ohme ePod installed by Octopus today. I have my meters on the outside of the garage wall but chose to put the chargepoint inside the garage, having checked the cable could pass under the garage door ok. I was surprised that the RCD was installed in separate box next to the outside meters rather than inside. The box is quite deep and projects into the side passageway somewhat. The installer did a tidy job and demonstrated charging at 6.6 kW before leaving. I need to look into changing my tariff now.

 

[siteguru]

How often do you need to charge? How many kWh are you typically adding when you charge?

And the $64k question ... are you prepared to time-shift other heavy usage (washing machine, dishwasher, tumble dryer) to the overnight period?