Outdoor socket for granny cable

cr-07

Hi all.

Just picked up a 2020 BMW 330e yesterday and unfortunately the 3-pin charger is too short to reach my current existing outdoor charger.

Using an extension cord is a big no-no I think?

If an extension cord won’t do, I was thinking about installing another external socket. I have an indoor socket that would go directly back to back with the ‘new’ outdoor socket.

My question really is this:

Does a PHEV need its own feed/circuit when using the 3-pin plug, or can it be plugged in to a socket that shares its feed/circuit with another socket?

Looking to do this as a DIY project, and maybe install a type 2 charger next year.

...Ghost...

OK, so the granny charger will draw around 10A, so if you feed from the existing outdoor socket, I would recommend that only one socket is used at a time unless the load is very low on the second socket.

I ran my outdoor socket in galvanised tubing, but this was part of a larger project in the front garden where I was running cable through conduit anyway.

MrMusician18

If you are going to the hassle of putting in a socket, you may as well put a 32a one in. You can use a converter plug in the meantime but you'll also be able to get a plug in type 2 charger as well.

Extension cord is not recommended as the plug in the charger has a thermal sensor to prevent overheating due to poor connection in the socket. The charger pulls the max current for a significant period of time so it is a risk. That said I have been known to use a 2.5mmsq lead to get me out of a pinch on occasion.

Gumbo

https://www.boards.ie/discussion/2058333561/outdoor-socket-for-granny-cable

No, as the granny cable will only draw 10a I believe. About 2kw.

Gumbo

https://www.boards.ie/discussion/comment/121684783#Comment_121684783

Outdoor socket doesn’t require wiring to be fed back to the consumer though, which is the issue here. An outdoor socket can be split from the internal socket in the other aid did the wall without a works other than a drill.

cr-07

Cheers all! Will pick up an extension cord for if I’m stuck, and will look at installing a 32a socket during the week.

Gumbo

https://www.boards.ie/discussion/comment/121685357#Comment_121685357

Extension cord = No.

And now days the cords are coming with warnings saying unsuitable for EV charging.

cr-07

If I got an extension cord that is able to handle 13a, would that not be okay? I can set the car to only draw 6a for example.

What would be the issue with using an extension cord? Overheating of the cord?

Gumbo

https://www.boards.ie/discussion/comment/121686247#Comment_121686247

Over heating of the cord. Constant draw on the extension lead.

The lead manufacturer tell you not to use an EV charger on it and the EV granny cable tells you not to use with an extension lead.

It might be grand for 364 days of the year. You have the info so you can decide on the element of risk of any now 👍

Buffman

https://www.boards.ie/discussion/comment/121686247#Comment_121686247

Personally the only issues I've seen with extension leads are when they are not used correctly. Mainly people with poor quality leads or poor socket wiring or coiled up leads that should have been unwound. Even at only 10A, I've seen these melt sockets and plugs without tripping anything, so not good. Lots of people don't even realise that the wind up roll extension leads have different ratings for wound and unwound. These would be the main reason manufactures don't recommend the use of extension leads. As mentioned above, I've noticed a lot of leads now say not suitable for EV charging, I'd guess they were having lots of issues with incorrect use.

A correctly specced good quality lead used correctly should not have any issues, especially if you are only using it at 6A as you plan. Back in the day before I got my first charger installed I worked off a granny charger at 10A on a 10m extension lead for well over a year without issue.

My main suggestions are to not use a wind up lead, just a normal good quality 13A one, and don't coil it up on itself in a pile, run it as neatly as possible, and don't use anything else on that socket at the same time as charging. Also goes without saying that the socket it's being plugged into should be up to scratch and not some relic left over from electrification.

On first use I'd recommend checking all the connections and lead for heat after about 10-20minutes, if there's excessive heat, discontinue.

I still have the lead in with the granny charger in case I'm ever stuck for it anywhere.

There are a few places selling granny charger extensions like this, there's some good safety advice at the bottom also:

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

To answer your other Qs:

"Does a PHEV need its own feed/circuit when using the 3-pin plug, or can it be plugged in to a socket that shares its feed/circuit with another socket?"

No, the whole reason granny chargers are rated at 10A and not higher is to allow them to run off the shared 13A socket circuits. The larger 16A+ chargers require their own dedicated circuits.

Edited for Typos.