Problems with home charging using the 3 pin plug charger

[Mike West]

Problems with home charging using the 3 pin plug charger
Hello, I have been charging my MG EV using the 3 pin plug home charger supplied with the car. However, whilst it worked well initially, the plug became very hot and damaged the socket. I replaced the socket and it worked fine again to begin with, but then the same thing happened. On examining the plug, I noticed that there had been arking across the chamfered ends, suggesting that the connection was inadequate for the current. When I measured the plug pin length, I found that it was about 1.5mm shorter than normal plugs, and I suspect that the smaller pin length has reduced the contact surface with the socket to a point where long term use results in the failure just described. Has anyone else experienced the same issue, and if so, how did you get round it? Many thanks, Mike

 

[Jomarkh]

Was the first socket you used installed for the job or an existing one inside the garage?
How long do you charge for and is it on an extension cable?
Are you planning on getting a 7.5kw charger unit?

 

[Lovemyev]

Hi Mike I have expressed my own thoughts over long term use of a Granny charger on a three pin plug.
I used a Granny unit myself on my previous PHEV for almost seven months, while waiting to get my wall box installed.
Other owners use the Granny on a daily basis and report no issues at all.
But a lot will depend on our usage case and the age / condition of your electrics.
Even with using a high quality electrical socket outlet etc, the 13 Amp plug did get warm after a while.
It also did the same when I used it while on holiday, at a different location.
If you are seeing brown / black burning at the socket outlet, then too much heat is being produced without any doubt.
I would strongly suggest having the regular socket charging outlet in its own dedicated circuit from the consumer unit and only use the best quality socket outlet that you can find on the market.
I used MK equipment for my charging socket outlet.
Run of the mill average quality socket outlets are not really advisable for pulling a high continuous load from a Granny cable.
I know the all meet the BS standard for a three pin outlet, but they are not all to the same quality unfortunately.
To avoid any excess heat, the wiring and quality of the equipment has to be 100% at all times.
A wall box is a better long term solution IMHO.
P.S. - Try and avoid using an extension cable if you can.
And never use it coiled up of course.

 

[Gomev]

Hi Mike I have expressed my own thoughts over long term use of a Granny charger on a three pin plug.
I used a Granny unit myself on my previous PHEV for almost seven months, while waiting to get my wall box installed.
Other owners use the Granny on a daily basis and report no issues at all.
But a lot will depend on our usage case and the age / condition of your electrics.
Even with using a high quality electrical socket outlet etc, the 13 Amp plug did get warm after a while.
It also did the same when I used it while on holiday, at a different location.
If you are seeing brown / black burning at the socket outlet, then too much heat is being produced without any doubt.
I would strongly suggest having the regular socket charging outlet in its own dedicated circuit from the consumer unit and only use the best quality socket outlet that you can find on the market.
I used MK equipment for my charging socket outlet.
Run of the mill average quality socket outlets are not really advisable for pulling a high continuous load from a Granny cable.
I know the all meet the BS standard for a three pin outlet, but they are not all to the same quality unfortunately.
To avoid any excess heat, the wiring and quality of the equipment has to be 100% at all times.
A wall box is a better long term solution IMHO.
P.S. - Try and avoid using an extension cable if you can.
And never use it coiled up of course.

Using an extension cable is perfectly fine so long as it is 13amp rated and used uncoiled. Many use these due to circumstances, particularly if on holiday.

 

[Headgas1]

I only use my granny charger with a good single socket extension lead for charging and I can report no issues whatsoever plugs hardly even get warm and the longest was about 14 hours but I only need to do this once a week so I’m not over using it.

 

[Kithmo]

The length of the pins on a 3-pin plug shouldn't affect the connection as they actually pass through the connections in the socket.
Someone else on here had a problem with the plug on the granny, IIRC the fuse was not tight in the fuse holder and their solution was to fit a replacement plug on the granny.

 

[Lovemyev]

I only need to do this once a week so I’m not over using it.

Low usage case, so experiencing excessive heat damage is very unlikely.
Also, it should be noted that charging on a Granny when feeding a PHEV that has a small battery, is only going to take about 4 hours total.
It is a completely matter for a high user case, who wishes to using a Granny to charge a full BEV with a much larger battery pack.
The unit will be pulling juice at a constant high rate for hours & hours on end on constant daily basis.
Then you have to question the longevity of this units ?.
Time will tell I guess ?.

 

[Alb]

Having the same fault with two different sockets certainly points the finger at the plug.
Remember that this unit is covered by warranty. I'd suggest asking your dealer for a replacement.

 

[Ozzie1989]

If you can put up with slightly slower charging times then you can purchase variable rate chargers such as this one.

Most 13a 3-pin EV chargers come with temperature monitoring within the plug, that's why they are bigger than a standard 13a plug. I'd like to hope MG's does too and yours is just faulty.