Home charging hot plug

[ms6189]

Hi guys ,

I have recently purchased my mg4 and started charging it soon as i got home but the plug of the extension which is connected to my car charger gets quite hot while in my home plug socket is this normal?

 

[Jomarkh]

Hi guys ,

I have recently purchased my mg4 and started charging it soon as i got home but the plug of the extension which is connected to my car charger gets quite hot while in my home plug socket is this normal?

Yes, but not in a good way, that is why a 7kW EVSE is the way to go.
Is the plug socket on a ring main or a new dedicated outside waterproof socket?
Are you using an extension lead? if so fully unwind it.

 

[Tig170]

Yes thats standard, you're pulling 10A+ for hours on end, simple fuses are not really upto the task these days. I also went for a 7kW EVSE as soon as possible for this reason.

 

[PristDean]

You should consider obtaining an appropriate extension cable if you need to use one. This is a good video on the subject

 

[ms6189]

Yes, but not in a good way, that is why a 7kW EVSE is the way to go.
Is the plug socket on a ring main or a new dedicated outside waterproof socket?
Are you using an extension lead? if so fully unwind it.

Ive connected the car charger plug to a wind up extension connected to my house

 

[GaryMG4]

I tried a 10hr test with mine, it drew 8-9 amps the whole time and wasn't even warm to the touch at the end of it. this was plugged direct into the ring main.

 

[ms6189]

You should consider obtaining an appropriate extension cable if you need to use one. This is a good video on the subject

Ive got a 13amp heavy duty wind up extension i think it should help?

 

[MoDolph]

You can reduce the charging current in the car. 6A or 8A are much safer when using an extension lead

 

[Rolfe]

I tried a 10hr test with mine, it drew 8-9 amps the whole time and wasn't even warm to the touch at the end of it. this was plugged direct into the ring main.

Mine's the same. I've tried 14-15 hours and the plug wasn't warm to the touch. My electrician said it helps that the socket is in the garage where it's cool, which helps any heat dissipate. But he said in effect it's as safe as anything else in view of the multiple layers of safety built into the electrical system - 13A fuse in the plug, garage sockets on their own circuit with a circuit breaker etc. I'm also lucky that the socket (which has a metal casing) is only 1.5 metres from the car's charging port when it's garaged, so I don't need an extension lead.

If a plug's getting hot it's a worry though, especially if the socket is inside the house. Like the others have said, make sure the extension cable is heavy-duty enough for the job and laid out flat, not tightly coiled.

Do you have any public charging facilities near your house? One thing I do to take the heat off the granny lead (literally) is to charge up for nearly an hour on a rapid charger that's only five minutes walk from my house, then bring the car home and just let it finish and balance-charge at home, which only takes a few hours. It helps that the rapid charger is both close enough to walk home from and only 30p per KWh though!

 

[Martinonline]

I agree you must have a heavy duty extension lead. If your problem is with the plug then you must look at the plug to check that the pins are shiney-bright and that, if it is not a moulded-plug that the incoming wires are properly connected tightly to the pins without any lost strands. Monitor the temperature as you charge, ensure air around the socket, Look for any burn marks.

 

[djenson]

toughleads.co.uk is your (expensive) friend for EV charging extensions

 

[siteguru]

Is it the plug (on the EVSE lead) that's getting hot? Or the one on the extension lead?

If the one on the EVSE, then maybe it's actually the socket of the extension where the problem lies rather than the plug of the EVSE, and the heat is just being conducted. Get the extension socket check out.

Also, fully unwind the extension lead when using it with the EVSE ... heat loss occurs due to cable resistance, and when the cable is coiled then the heat compounds itself.

 

[Kithmo]

When buying an extension, look at the continuous current rating not just the maximum.
The Granny pulls about 9A, so 10A continuous (or preferably more) should be ok.
Make sure the plugs and sockets are a good tight fit.

 

[Lovemyev]

Ive connected the car charger plug to a wind up extension connected to my house

If it's the wind up type that I have a picture of in my head, then hell no !.
It should NOT be coiled up regardless and please ensure that the extension lead is suitability rated to carry that heavy load for long periods of time.
Extension leads usage is okay ....... but I would prefer to limit there use TBH.
I do see them more as a short term option purely myself.
Check the lead is three core and has a cross section value of NO less than 1.5mm.
If it's 2.0mm that's fine, but please no lower than 1.5mm ( it will be printed on the outer casing of the flex ).
After the Granny has been in use for a couple of hours, the plug top will be warm to the touch.
You will find it warmer at LIVE conductor of the three pin plug.
This is to be expected, if its MAD hot then that is not right, or safe.
Once a week, remove the three pin plug from the socket outlet and if it tight to remove and there is any signs of brown scorch marks on the outlet, then clearly it is getting too hot and needs addressing ASAP.
Ideally you would have a stand alone outlet installed on a dedicated circuit supplied from your C.U.
When charging an EV from home, if it's a Granny or a Wall Box, the condition of the wiring and the installation ( in the case of a wall box ) has to be 100% or excessive heat will be generated as a result.
Because the Granny lead has a three pin plug fitted, many people regard this as any other appliance they have and treat it accordingly.
I am willing to bet there is very little other electrical appliances that are rated as the same and are intended to be pulling this type of load for hours on end.
This is not your average lawn mower or even a microwave oven you are plugging in here.
There is a clue provided, when you study the thickness of the lead fitted on the Granny unit.

 

[Tig170]

Is it the plug (on the EVSE lead) that's getting hot? Or the one on the extension lead?

If the one on the EVSE, then maybe it's actually the socket of the extension where the problem lies rather than the plug of the EVSE, and the heat is just being conducted. Get the extension socket check out.

Also, fully unwind the extension lead when using it with the EVSE ... heat loss occurs due to cable resistance, and when the cable is coiled then the heat compounds itself.

I've seen both, not a hot plug, but certainly warm. Likewise any extension lead needs to be fully unwound, Ive just check the label on a few that i have sitting here: both say 720W wound & 3120w unwound, i.e. never ever try to charge your car with wound reel, and always charge fully unwound, so its fine if your at grannies for a weeks holiday or so, but not a permament solution.

We've just booked a break away for a few days, had no idea before booking but the destination has 7kw charging run by a company / app called VendElectric @ 20p / unit (they seem to be everywhere) = sensible pricing = dont need to risk anyones lives using an extension lead / granny charger out of the window overnight (as well as being very rude, if you dont ask beforehand either).

There is a clue provided, when you study the thickness of the lead fitted on the Granny unit.

.... thats what struck me also (it looks like its 4mm cable?) = better check this out!

 

[Rolfe]

I've seen both, not a hot plug, but certainly warm. Likewise any extension lead needs to be fully unwound, Ive just check the label on a few that i have sitting here: both say 720W wound & 3120w unwound, i.e. never ever try to charge your car with wound reel, and always charge fully unwound, so its fine if your at grannies for a weeks holiday or so, but not a permament solution.

We've just booked a break away for a few days, had no idea before booking but the destination has 7kw charging run by a company / app called VendElectric @ 20p / unit (they seem to be everywhere) = sensible pricing = dont need to risk anyones lives using an extension lead / granny charger out of the window overnight.

Lucky you! The type 2 chargers outside my friend's house (where I went for a few days break) cost 69p per unit. Absolute rip-off.

But I was only there for three nights, and I didn't need a huge amount of charge anyway, so I used them anyway, rather than the plastic socket in my friend's garage. It would probably have been OK, but why chance anything when there are type 2 chargers about 50 yards away.

 

[Grriff]

No plug or socket should get hot in use provided the plug fuse is the correct rating for the cable.
If this happens it's possibly a result of a loose connection. If you have the expertise, check all the cables are screwed tight into their terminals and the fuse is tight in its holder. If it's still hot, stop using the cable, try another or get professional advice.

 

[Staffex]

It’s surprising how much energy gets lost in connecting cables. I thought the perfunctory 6mm2 swa cable (rated at between 44 and 66 amps depending on how it’s run) used to connect 7kWh chargers to consumer units, was overkill. That was until I did some basic calculations…
3-core swa typically has a resistance of 4.6 ohms per kilometre, which equates to 0.115 ohms in the 25m run between my house and garage. So the combined Live-Neutral resistance is 0.23 ohms. At 30 amps (7.2kWh) the potential difference will be 6.9 volts - which means that in the worst case 207 watts are being wasted as heat in the cable alone.

 

[WonkoTheSaneUK]

It’s surprising how much energy gets lost in connecting cables. I thought the perfunctory 6mm2 swa cable (rated at between 44 and 66 amps depending on how it’s run) used to connect 7kWh chargers to consumer units, was overkill. That was until I did some basic calculations…
3-core swa typically has a resistance of 4.6 ohms per kilometre, which equates to 0.115 ohms in the 25m run between my house and garage. So the combined Live-Neutral resistance is 0.23 ohms. At 30 amps (7.2kWh) the potential difference will be 6.9 volts - which means that in the worst case 207 watts are being wasted as heat in the cable alone.

The easiest way to locate heat loss is to see where the neighbourhood cats like to hang out.

(A Starlink dish for example)