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Home Charging - Extension Cable

Tabby

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Hi

Does anyone use an extension wire to charge the car and would you be kind to recommend a waterproof cable please?

My car is parked in a car park and not directly outside my house, I would probably need an extension that is at least 25m long.

Thank you.
 
Depends on which charger he is using. As it is at home probably hooking up to a 13A socket the cable will be fine.
 
If the cable is over rated for the load this is fine, using an underrated cable over that distance is really not recommended.
Of course any spare cable should not be coiled up either !.
“Go big or go home” is an expression used by our friends in the USA 🤣.
The extension cable I made for exceptional usage cases, is wiring in 2.5mm flex.
Over rated cable size - Yes !.
Bothered - No !.
No way that is going to suffer from any load carrying capacity or excess heat being generated.
Not a big lover of using extension cable for charging myself, but needs must I guess.
 
The cable suggested is 2 5 mm and since he needs 25M length unlikely to be coiled
I have just taken a quick look at the spec's in the link provided and it's a little unclear on the cross sectional size of this cable, is it 1.5 or 2.5 mm ?? .

"The maximum amount of current that a conductor can safely handle at any given time.
The larger the cable size, the more current, in amperes, it will be able to conduct.
This is an important aspect of any wiring system because it determines the maximum load that can be connected to the circuit.

For instance, a 1.5mm2 wire has a standard current capacity rating of 10 amps (but it can carry up to 20 amps). It is, therefore, used primarily in lighting systems because most of them demand up to 7 amps, which falls within the “safe zone.”

Of course, the same wire can work in a circuit fused at 13 amperes, but that’s dangerous because it’s right on the edge. Therefore, it’s recommended that you use a 2.5 mm square wire for such circuits because it has a current rating of 13.5 amps, though it can handle up to 25 amps.


Orange EV Cable 2023-01-14 at 18.13.11.png
 
Hi

Does anyone use an extension wire to charge the car and would you be kind to recommend a waterproof cable please?

My car is parked in a car park and not directly outside my house, I would probably need an extension that is at least 25m long.

Thank you.
You do have other things to think about as well, this could be a trip hazard if you have the cable into a car park and gos over a footpath. How to keep the scocket near the car dry so it doesn’t trip your electricity. Can you get the car in the same place each time.
 
I have found, from practical experience, that the domestic charger (which has 'Do not use with an extension lead' written on it) is unreliable with an extension cable rated at 13amp, but works OK with an extension rated at 16amp, which was what I used in France as that's the standard there.
 
HI there. Been using toughleads.co.uk EV extension lead(s) for the longest of times, even got a custom one in orange. Great people to deal with, and a extension lead that fits the bill.

I have just taken a quick look at the spec's in the link provided and it's a little unclear on the cross sectional size of this cable, is it 1.5 or 2.5 mm ?? .

"The maximum amount of current that a conductor can safely handle at any given time.
The larger the cable size, the more current, in amperes, it will be able to conduct.
This is an important aspect of any wiring system because it determines the maximum load that can be connected to the circuit.

For instance, a 1.5mm2 wire has a standard current capacity rating of 10 amps (but it can carry up to 20 amps). It is, therefore, used primarily in lighting systems because most of them demand up to 7 amps, which falls within the “safe zone.”

Of course, the same wire can work in a circuit fused at 13 amperes, but that’s dangerous because it’s right on the edge. Therefore, it’s recommended that you use a 2.5 mm square wire for such circuits because it has a current rating of 13.5 amps, though it can handle up to 25 amps.


View attachment 14480
Current rating of cable is depending on conductor size (Duh) and the insulation rating. The higher temperature the insulation is rated for, the higher the current capability of the wire. 1.5mm2 is absolutely fine for the granny charger, which does not pull more than 10 amps. The issue with using an extension is the plug and socket, in the granny chargers plug there should be a thermistor which detects if the plug is getting too hot, but obviously this protection is removed when using an extension. If there is any poor connections or something causes there to be a fault where 11amps is used for insance, i2r will mean that lots of excess heat is dumped in that area. This can mean things like
-Fuse gets so hot it melts the plug and socket
-Wiring in the socket gets so hot it starts to melt the installation and potentially cause a short circuit or at worse a fire.

For this reason, it is essential for @Tabby to get the circuit they intend to use for charging the car checked before they use it. In my case, me and a qualified electrician friend ran a new run of 2.5mm2 twin and earth from a brand new rcbo to an outdoor socket, where then the toughleads.co.uk extension take it to the granny charger which plugs into the car. In this way there is a entre dedicated run of wire for the car to charge off, not impacting on the ring main.
 
Current rating of cable is depending on conductor size (Duh) and the insulation rating. The higher temperature the insulation is rated for, the higher the current capability of the wire. 1.5mm2 is absolutely fine for the granny charger, which does not pull more than 10 amps. The issue with using an extension is the plug and socket, in the granny chargers plug there should be a thermistor which detects if the plug is getting too hot, but obviously this protection is removed when using an extension. If there is any poor connections or something causes there to be a fault where 11amps is used for insance, i2r will mean that lots of excess heat is dumped in that area. This can mean things like
-Fuse gets so hot it melts the plug and socket
-Wiring in the socket gets so hot it starts to melt the installation and potentially cause a short circuit or at worse a fire.

For this reason, it is essential for @Tabby to get the circuit they intend to use for charging the car checked before they use it. In my case, me and a qualified electrician friend ran a new run of 2.5mm2 twin and earth from a brand new rcbo to an outdoor socket, where then the toughleads.co.uk extension take it to the granny charger which plugs into the car. In this way there is a entre dedicated run of wire for the car to charge off, not impacting on the ring main.
I am well aware (duh) that 1.5mm will handle the draw from the Granny unit and that tough leads use 1.5mm flex on their extension cables, all the info and specs can be found on there website or by contacting directly.
I seem to remember that the OP intended to run this extension cable over a very long distance ( about 25 metres I seem to remember ) also ?.
Has this extra long cable run been accounted for on cable size I wonder ?.
Tough cables are very supportive and helpful.
In my case, I already had just less than half a roll of unused 2.5mm flex on a drum ( which is over kill rated I know ) so I used it !.
I can’t see any problem with that to be honest, my dedicated 13 Amp socket outlet I used to charge my car with by the Granny, before having my wall box installed, was run in a very similar way to yours on its own dedicated circuit.
My extension cable has received very little use, because I only consider its use when going away for a few days and the charging infrastructure in that location is extremely poor.
Not a big lover of extension cables myself, but if needs must you have little choice 😞.
 
Hi

Does anyone use an extension wire to charge the car and would you be kind to recommend a waterproof cable please?

My car is parked in a car park and not directly outside my house, I would probably need an extension that is at least 25m long.

Thank you.
This is what I use, amazon approx £22
 

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Hi

Does anyone use an extension wire to charge the car and would you be kind to recommend a waterproof cable please?

My car is parked in a car park and not directly outside my house, I would probably need an extension that is at least 25m long.

Thank you.
The thing here is to realise that the longer the cable the thicker the diameter has to be to cope with maximum current within the cable for the longer distance. It gets complicated but best advice is to buy from a reputable source that know their business. I bought a 10 metre cable because the supplied 5 metres was not nearly enough. The cable diameter has no difference between the two as the extra length was not significant. So buy carefully. Don't go for 16 amp cable for your length if you will use 16 amps continuously unless the cable is 'rated' for such use. Different types of insulation allow for different current usage so as I say, buy from a company that knows what they are talking about.
 
It was the third 25m extention cable I bought but the only one that the socket would take the thicker cable of the granny lead. It has RDC protection. Thank you ‘Tough Leads’
 

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I use this and absolutely no problem, I make sure I only charge 6 hours maximum at one go.

I don't have a dedicated charger and been using 3 pin charger since beginning, no issue
 

I use this and absolutely no problem, I make sure I only charge 6 hours maximum at one go.

I don't have a dedicated charger and been using 3 pin charger since beginning, no issue
Fine for granny charging...
 
The starter of the thread did say they require at least a 25m cable so screw fix at 10m not suitable.
The ’Tough Lead’ (with RCD protection) is also rated IP66 waterproof, meaning it remains watertight when subject to powerful water jets from any direction.
Unfortunately you only get what you pay for, with shipping and VAT, cost £77.78
 
Hi Tabby
As the granny charger draws about 2.4 kw ( what i see on my electricity usage screen) thats about 10A continious usage. I needed a 10m extension lead and I remember reading early on in the forum someone recommended

PRO XT 13A 1-GANG UNSWITCHED EXTENSION LEAD 10M​

from screwfix.
I basically plug it into a mains socket in the garage, it goes under the door, and i have the socket end of the extension lead go into the boot of my car and the granny charger is plugged into that. The granny charger is also left in the car and the lead from the granny charger comes out and plugs into the car type 2 socket. I make sure the extension and charging cable are not near the closing mechanism then close the boot. This means i can leave it ( hopefully safe and secure) when charging over night.
I have been doing this for 18 months and not had any issues.

I am no expert on these matters but try to use common sense so below is just my thoughts from this perspective.

I see you want a 25m cable and i see they do do one, but its on a reel , so remember if you go for this type always unwind it fully or the cable left on the reel ( unwound) has a chance of melting due to the 10 A flowing through it.

So you could buy a 25m one , try it ( make sure things dont get really too hot ) if it works ok then you are fine , it it does notwork then you can always return it.
 
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