Using a normal extension lead outside

[prospectivebuyer]

Going away this week and taking my granny charger to plug in when I get there. Is using a normal 5m indoors extension lead a stupid idea for outside for 1 night?

 

[pollenface]

It should be fine. Indoor cables are often of a lighter guage cable, which may warm a little with constant 8amp draw, be mindful.

 

[slmorgan42]

Going away this week and taking my granny charger to plug in when I get there. Is using a normal 5m indoors extension lead a stupid idea for outside for 1 night?

May be stating the obvious but with the current weather do watch out for rain on the cable if outside

 

[Jomarkh]

It should be fine. Indoor cables are often of a lighter guage cable, which may warm a little with constant 8amp draw, be mindful.

The current is a constant 10A in the UK.
Check that it is rated at 13A and fully unwind it.
Just check it every hour to see if it is getting hot, warm is normal.
I take a socket tester with me and an RCD plug through unit, just to be on the safe side, as you don't know the state of the house electrics.

 

[Lovemyev]

Should be okay as a one off situation.
Check on the cable rating, it is printed on the outside sheathing.
It needs to be no less than a cross rating section of 1.5mm.
Larger ( 2.5mm ) is fine, but not any smaller than 1.5mm.
Some of the cheap windup ones are only rated at 0.75 / 1.00mm - NO GOOD !.
This size flex will over heat and is dangerous.
Okay for your Xmas lights etc but that’s it.
If the cable is in good external condition and it gets a little wet, there is little risk here.
It’s the socket outlet that your Granny lead plugs into, that is the vulnerable part that needs to be protected from the rain.
Try and keep the socket outlet off the ground and as a temporary measure, do you have a large plastic storage container that could be used to put over the socket outlet to shield it from the rain ️ ?.
If you intend to use a socket outlet externally, then it should be suitably IP 55 / 65 rated.
This rating covers both dust and water ingress.
As other members have said, monitor the heat being produced at the three pin plug that you are using to power your extension.
The plug top WILL get warm to the touch, which is completely normal, but if it gets mad hot to touch, then stop.
The plug on the charger is unlikely to get hot because it carrying a heavy duty plug and cable.

 

[Ian Key]

Going away this week and taking my granny charger to plug in when I get there. Is using a normal 5m indoors extension lead a stupid idea for outside for 1 night?

I take it you have asked permission to charge the car overnight? There has been some arguments in the news recently about some rental property owners objecting to EVs charging up using their electricity.

 

[pollenface]

The current is a constant 10A in the UK.

Okay, supplied charger in Australia is 8a

 

[Rolfe]

I bought a purpose-made EV charging extension cable for this. It has a cover over the socket that snaps shut when the granny charger is plugged in, and even fittings for a padlock to prevent interference. Maybe overkill, but carrying it and the granny charger on long journeys seems like the equivalent of the 5-litre can of petrol in the boot.

EV granny charger 13A weatherproof extension lead

High quality 13A weatherproof outdoor waterproof extension leads heavy duty 1.5mm H07RN-F rubber cable. RCD option. IP66. Designed specifically to overcome the issue created by chunkier plugs on electric vehicles (EVs). 2m, 5m, 10m, 15m, 20m and 25m lengths.

toughleads.co.uk

Note that they have various lengths up to 15 metres available.

 

[prospectivebuyer]

I take it you have asked permission to charge the car overnight? There has been some arguments in the news recently about some rental property owners objecting to EVs charging up using their electricity.

they’ll never know

Should be okay as a one off situation.
Check on the cable rating, it is printed on the outside sheathing.
It needs to be no less than a cross rating section of 1.5mm.
Larger ( 2.5mm ) is fine, but not any smaller than 1.5mm.
Some of the cheap windup ones are only rated at 0.75 / 1.00mm - NO GOOD !.
This size flex will over heat and is dangerous.
Okay for your Xmas lights etc but that’s it.
If the cable is in good external condition and it gets a little wet, there is little risk here.
It’s the socket outlet that your Granny lead plugs into, that is the vulnerable part that needs to be protected from the rain.
Try and keep the socket outlet off the ground and as a temporary measure, do you have a large plastic storage container that could be used to put over the socket outlet to shield it from the rain ️ ?.
If you intend to use a socket outlet externally, then it should be suitably IP 55 / 65 rated.
This rating covers both dust and water ingress.
As other members have said, monitor the heat being produced at the three pin plug that you are using to power your extension.
The plug top WILL get warm to the touch, which is completely normal, but if it gets mad hot to touch, then stop.
The plug on the charger is unlikely to get hot because it carrying a heavy duty plug and cable.

I was thinking about putting it under the car out of the way of rain etc , but maybe a plastic container is more suitable

 

[Lovemyev]

I was thinking about putting it under the car out of the way of rain etc , but maybe a plastic container is more suitable

Placing it under the car will help keep it dry of course, but in the very very unlikely event that the unit developed a fault, under the car may not be the best location then .

 

[Rolfe]

they’ll never know

Maybe not, but they may check. Considering that the cost of the electricity isn't likely to be great, it might be worth offering them the cost, if only to avoid creating ill-will against future EV drivers visiting.

I usually say the car draws about the same as a fan heater running continuously, maybe between 50p and 55p an hour. You'd probably need to charge for 18 hours to bring it up to a tenner.

 

[prospectivebuyer]

Maybe not, but they may check. Considering that the cost of the electricity isn't likely to be great, it might be worth offering them the cost, if only to avoid creating ill-will against future EV drivers visiting.

I usually say the car draws about the same as a fan heater running continuously, maybe between 50p and 55p an hour. You'd probably need to charge for 18 hours to bring it up to a tenner.

Another angle is if they have not specified anywhere about the usage of electricity for charging then why can’t I ? As I’m renting the home for 3 days I expect to use it as I would my own home over that time period. Maybe owners need to be a bit more savvy if they don’t want people doing this as it will only happen more often going forwards

 

[johnb80]

Another angle is if they have not specified anywhere about the usage of electricity for charging then why can’t I ? As I’m renting the home for 3 days I expect to use it as I would my own home over that time period. Maybe owners need to be a bit more savvy if they don’t want people doing this as it will only happen more often going forwards

Yep that's the right outlook, at home you would pay for your electricity (I assume) and therefore here you should pay too.

 

[prospectivebuyer]

Yep that's the right outlook, at home you would pay for your electricity (I assume) and therefore here you should pay too.

So when you use an air bnb you normally give them an extra tip towards the electric for using the shower, oven and watching the tele?

 

[Ian Key]

I think the problem is electric showers and ovens aren't on for 12 hours drawing 3kW continuously so you are also trusting their electrics are up to spec and can handle that loading without any problems.

They are often on tight margins and their rental price is based on the average use of electricity. Surely the correct thing to do is ask if it's OK.

 

[GaryMG4]

I'm heading off to Yorkshire soon and will be asking the owners about using the granny lead.

 

[Ruislip Resident]

I filter on EV charging as one of my search parameters. I would always expect to pay for what I use to charge. If the charging available / allowed was via a granny instead of a dedicated chargepoint, I would want to be certain the electric socket I could plug into is up to spec to take it. Eg a proper electrician installed external socket. Safety would come first, then convenience, then cost.

 

[prospectivebuyer]

Fair enough! I was going to ask anyway but just assumed it would be no issue, will double check

 

[Jomarkh]

We were away for a week in Scotland 4 different places. One said there insurance didn't cover EV charging two said no and one was OK with it. I can select 8A on my granny EVSE.

 

[Rolfe]

I think the reputation of the EV community is worth considering. Someone who asks politely and offers to pay (and doesn't throw a strop if for some reason the answer is no) is building up goodwill for all of us. Someone who leaves a holiday rental holding a larger than expected electricity bill without saying a word is going to foster ill will against the next EV driver who shows up, however polite and considerate he is.

There's also the question of electrical safety, and as @Jomarkh pointed out, insurance. If, perish the thought, the socket does overheat overnight and starts a fire (or even just melts), your cover is blown in the most embarrassing of circumstances. If the property isn't insured for EV charging, you could be in a serious mess.