EV extension lead 3 pin - such a thing?

[Abe Froman]

Hello all,

I have been bamboozled by information I'm afraid and now need a sensible answer...which hopefully I'll get here.

We have a 2021 BMW i3S but are currently renting our house so no wall socket, just a 3 pin (takes a while, but fine)

Unfortunately there is no outside socket and having the window open is freezing.

What we need is an extra 10m on the charger. But have been told an extension lead is a no-no...or is it?

Can you buy specific EV extension leads? I have searched and researched and am a bit lost tbh.

Thanks.

Would this work?
https://toughleads.co.uk/collections/ev-electric-v...

[xx99xx]

Any 13a exterior lead should do. But not a coiled one. And providing your house wiring is up to it also i.e. a high load for an extended period of time can overheat poor wiring.

I'm not a qualified electrician but this was the advice I received a few years ago when I asked a similar question on speakev.

[MOBB]

I used one for a few months while I was waiting to move house, no issues.

I did unwind it fully though

[Scrump]

I used to use one with my PHEV. Made sure it was rated for the full 13 amps and always fully uncoiled it. It had a ‘waterproof’ socket on the end for the 3 pin plug.

ETA it was a masterplug outdoor extension like this:

[SWoll]

We've used one of these for months charging multiple EV's. No issues and doesn't even get warm.

https://www.amazon.co.uk/gp/product/B0083GLMKU/ref...

If the extension itself needs to be outside you'll obviously also need a waterproof charging box for the charger block.

https://www.amazon.co.uk/DEWENWILS-Weatherproof-El...

[ruggedscotty]

good quality lead and plug socket - thats the important bit, and also to unwind the lead to allow it to keep cool. There are lots of cheap leads out there designed for low loads, never having to run something power hungry for an extended period of time. Could always make up your own lead, using decent flex linked to good weatherproof plug and socket.

https://www.cef.co.uk/catalogue/products/1500420-1...

also bear in mind that your taking an electrical earth out side of the house and what risks that brings. minimal I know. but best pointed out.

[Abe Froman]

Brilliant, thank you all!

The logical part of me said yes, it's fine. But then you start reading...best not to read.

Cheers.

[ashenfie]

Though that extension cables are a bit of a no no for charging EV, anyway if thats the way you want to go, I would definitely get one with an RCD

[ruggedscotty]

ashenfie said:

Though that extension cables are a bit of a no no for charging EV, anyway if thats the way you want to go, I would definitely get one with an RCD

Nope extension cables are okay - as long as they are substantial and designed for what they are being used for. id stay away from an RCD on the extension lead or the like, you want the RCD in the house protected from knocks and and weather. You will find that the majority of boards have RCD's on them so an extra RCD wont really give you any more protection.

[jev]

I'm using a standard 13A extension lead (uncoiled). But dialling down the charge current to 8A (from 10). Takes a little longer but seems fine.

[Daaaveee]

Abe Froman said:

Hello all,

I have been bamboozled by information I'm afraid and now need a sensible answer...which hopefully I'll get here.

We have a 2021 BMW i3S but are currently renting our house so no wall socket, just a 3 pin (takes a while, but fine)

Unfortunately there is no outside socket and having the window open is freezing.

What we need is an extra 10m on the charger. But have been told an extension lead is a no-no...or is it?

Can you buy specific EV extension leads? I have searched and researched and am a bit lost tbh.

Thanks.

Would this work?
https://toughleads.co.uk/collections/ev-electric-v...

The Toughleads weatherproof extensions are great, I used a 10m one for an i3 3 years ago before I got my charge point installed.

[springfan62]

Daaaveee said:

Abe Froman said:

Hello all,

I have been bamboozled by information I'm afraid and now need a sensible answer...which hopefully I'll get here.

We have a 2021 BMW i3S but are currently renting our house so no wall socket, just a 3 pin (takes a while, but fine)

Unfortunately there is no outside socket and having the window open is freezing.

What we need is an extra 10m on the charger. But have been told an extension lead is a no-no...or is it?

Can you buy specific EV extension leads? I have searched and researched and am a bit lost tbh.

Thanks.

Would this work?
https://toughleads.co.uk/collections/ev-electric-v...

The Toughleads weatherproof extensions are great, I used a 10m one for an i3 3 years ago before I got my charge point installed.

+1 I have one for use away, a standard extension is not suitable for such a high continuous load and will almost certainly overheat at the plug.
It's not worth the risk.

[SWoll]

springfan62 said:

+1 I have one for use away, a standard extension is not suitable for such a high continuous load and will almost certainly overheat at the plug.
It's not worth the risk.

Months of nightly use would suggest that isn't the case (barely gets warm), but agree the tough leads option is the best choice.

[somouk]

The electrician who fitted my outdoor socket mentioned he had seen a lot of people using cheap sockets and having the faceplate crack due to the continuous load in these 3 scenarios:

1. Car charging
2. Hot tub heaters
3. Grow houses

Just keep an eye on the socket and make sure the extension is rated high enough for the wattage and uncoiled, should be fine.

[gmaz]

Scrump said:

I used to use one with my PHEV. Made sure it was rated for the full 13 amps and always fully uncoiled it. It had a ‘waterproof’ socket on the end for the 3 pin plug.

ETA it was a masterplug outdoor extension like this:

I bought one of these and found that it got warm, and also the socket cover didn't clip shup over the chunky granny charger plug, so I returned it and got a toughleads one.

[agent006]

Our Leaf has charged on a 10 metre 3 pin extension every night for nearly two and a half years now. It's only a 10amp charger so there's a fair bit of headroom on a 13amp extension.

I remember reading that the actual charger itself has temperature sensors in the plug, which I assume is why it's not recommended to run an extension as that obviously doesn't. Though if it's getting hot enough to throttle the charge to protect its own plug, then you'd assume the extension plug would be a similar temperature and protected by association.

[5s Alive]

Made my own from 10m of 1.5mm2 cable. Had to source the cable, plug and socket from 3 different suppliers as orange seems to be in short supply.
Have also carefully modified (drilled holes) a Tupperware type clear plastic container to house the charger plug/socket combination if necessary.

Solely for emergency access to 13a supplies and most likely only when travelling however I'll avoid doing so if at all possible although some of our previous holiday destinations appeared quite happy to provide overnight top-ups to those who embraced EV some time ago.

[dhutch]

5s Alive said:

Made my own from 10m of 1.5mm2 cable.

See also
https://www.screwfix.com/p/masterplug-13a-1-gang-u...

As said, it is only frown apon because there are extensions which are not rated at the full 13A due to 'undersize' cable, and people who dont fully uncoil a coiled lead even when using it for a high-current high-duty application.

[5s Alive]

dhutch said:

5s Alive said:

Made my own from 10m of 1.5mm2 cable.

See also
https://www.screwfix.com/p/masterplug-13a-1-gang-u...

As said, it is only frown apon because there are extensions which are not rated at the full 13A due to 'undersize' cable, and people who dont fully uncoil a coiled lead even when using it for a high-current high-duty application.

And cheaper than mine too had it not been for one of the sellers issuing a refund in error and then telling me to keep the cable with their compliments after I had offered to pay again.

[ruggedscotty]

https://toughleads.co.uk/products/ev-extension-lea...

https://toughleads.co.uk/collections/ev-electric-v...

https://toughleads.co.uk/pages/safely-charging-you...

these get good rep - bit pricy but they do the trick