UK domestic socket charging

[mikgle]

There is a lot of discussion on various youtube sites (eg efixx) ref ev charging using a 3 pin granny lead i.e.should you do it? is it dangerous? etc. I wonder how many of you use this method, either occasionally or even all the time? I am an electrician and can see both sides of the argument.

For information, you can buy (eg Halfords) an ev charging socket for the purpose, price £49.95 Is anybody using one of these? I would be interested in how they find it.. Many thanks.

 

[webhiker]

Short answer: No
Too slow, too risky, too cumbersome, too, too, too, no I just don't have it in my plans. I do not even own a granny charger. I did for a previous car, and it just took up space in my shed

 

[tsedge]

There is a lot of discussion on various youtube sites (eg efixx) ref ev charging using a 3 pin granny lead i.e.should you do it? is it dangerous? etc. I wonder how many of you use this method, either occasionally or even all the time? I am an electrician and can see both sides of the argument.

For information, you can buy (eg Halfords) an ev charging socket for the purpose, price £49.95 Is anybody using one of these? I would be interested in how they find it.. Many thanks.

The main concerns are:

• Is the household wiring suitable? Ideally you'd have a dedicated modern circuit.
• Is the granny charger well made? Some cheap imports enable too high a current draw.
• Are you limiting the current? Many homes have wiring limited to 10A continuous, but this depends on people limiting the AC current draw in the car or the granny (if it provides this).

As an occasional charger there's no problem. The main concerns are about repeated use degrading already poor wiring and eventually leading to fires. People think if it works once it will always work.

That and the fact that granny chargers don't protect against PEN faults, like home chargers do.

That said, fires seem to be very rare.

Oh and there was a survey about the prevalence of people using coiled extension leads and leaving it all out in the rain.

If you are knowledgeable and savvy, there's no problem. But I suspect we'll need more laws for the stupid and ignorant.

 

[mikgle]

Short answer: No
Too slow, too risky, too cumbersome, too, too, too, no I just don't have it in my plans. I do not even own a granny charger. I did for a previous car, and it just took up space in my shed

I suppose if you hsve s proper chsrger theres no need, altho I do sometimes use one to soak up any surplus solar power. And when visiting relatives

The main concerns are:

• Is the household wiring suitable? Ideally you'd have a dedicated modern circuit.
• Is the granny charger well made? Some cheap imports enable too high a current draw.
• Are you limiting the current? Many homes have wiring limited to 10A continuous, but this depends on people limiting the AC current draw in the car or the granny (if it provides this).

As an occasional charger there's no problem. The main concerns are about repeated use degrading already poor wiring and eventually leading to fires. People think if it works once it will always work.

That and the fact that granny chargers don't protect against PEN faults, like home chargers do.

That said, fires seem to be very rare.

Oh and there was a survey about the prevalence of people using coiled extension leads and leaving it all out in the rain.

If you are knowledgeable and savvy, there's no problem. But I suspect we'll need more laws for the stupid and ignorant.

I agree with most of your points, however concerning PEN faults no other appliance plugged in is protected either, to be fair! I have replaced sockets which have burnt out but this can apply to normal use or shower switches; its usually poor (loose) terminations cause it. I also believe the socket switch is a weak point, due to the small contacts.. so its interesting that the so-called ev socket looks as tho its switchless.

Are you limiting the current? Many homes have wiring limited to 10A continuous, but this depends on people limiting the AC current draw in the car or the granny (if it provides this).

as far as I know, the granny charger control box limits the current to 10A, on mine it says it on the label.

 

[tsedge]

I agree with most of your points, however concerning PEN faults no other appliance plugged in is protected either, to be fair! I have replaced sockets which have burnt out but this can apply to normal use or shower switches; its usually poor (loose) terminations cause it. I also believe the socket switch is a weak point, due to the small contacts.. so its interesting that the so-called ev socket looks as tho its switchless.

Yes, usually bad connections cause high resistance promoting wear and tear through thermal expansion and then more heating and higher resistance - eventually triggering a burnt socket or junction.

as far as I know, the granny charger control box limits the current to 10A, on mine it says it on the label.

Yes, some dodgy imports were reported doing 13A (or even 15A!), if buying off AliExpress, for example.

And 10A continuous for hours and hours may be too much for old wiring (or if on shared circuit) so 6A or 8A much better.

 

[Jomarkh]

I used the MG granny until I got a 7kW EVSE installed.
If away I use a Kia granny which I can set to 8A which seems a lot safer

 

[mikgle]

And 10A continuous for hours and hours may be too much for old wiring (or if on shared circuit) so 6A or 8A much better.

A specific radial circuit is ideal ie one that just goes to that socket but a spur off the ring circuit would also be fine, as long as the same size wires are used ideally 2.5mm minimum. Having said that, 1.5mm wires take 13A.. but you are right, all wiring terminations and fittings, including the plug, should be inspected for soundness and signs of charring. Cheap enough to replace a socket really.. ideally using a switchless one but always remember to switch off at the car first before unplugging, that goes for any type of connection.

 

[Martinonline]

I used my MG granny charger for a year before fitting an EVSE last month. It was used plugged into a switchless outside socket on a short-run radial from the consumer unit with a 20amp MCB (fitted 2007). To reach the car I had to use a 15m single socket extension lead to a waterproof box.

I saw no degradation to the sockets or plugs and the plugs did not get excessively warm.

As @tsedge says your electrical installation determines the risk. Warning: Reported on this forum was someone who used a multi-socket extension block that became severely overheated and melted.

 

[Rolfe]

I used one for over a year before I got my Zappi, and still use it from time to time for particular reasons. However, I'm lucky enough to have a garage with its electrics on a dedicated circuit, and its power points are metal-jacketed, not the usual plastic. I have never felt the plug even faintly warm, even the times I did a full 26-hour charge from <10% to 100%. The pins on the plug are still as pristine as the day I got the car.

However, while visiting a friend with a big solar array on a FIT tariff on a sunny day, we thought we'd try swiping some free sunshine for the car. I used a purpose-made EV extension lead (my friend initially produced a puny-looking domestic extension lead, and I said, I don't think so) and we didn't charge for very long as I had to go, but in that time the plug and socket had become quite warm to the touch. There was no sign of any damage, and I've felt warmer plugs in my house from time to time (Christmas tree lights, and a fan heater), but I wouldn't have been comfortable leaving it overnight.

 

[Narrowgauge725]

I did for years admittedly on a PHEV and that was with an extension cable, everything was good quality and never had any issues.

 

[Archev]

I used to have a nice little sideline when I serviced and repaired showers. I always carried a couple of surface and especially pull cord switches in the car. If the terminals weren’t tightened with a decent broad screw driver and the user liked a long shower some of those cheaper switches didn’t last too well.
Very, very often the customer would then point out the length of the cord - even after I’d pulled it through, re- knotted it and trimmed it off. I had instances in old castles and mansion type properties where I needed to change the cord for new, even longer ones ?. I did see old bits of cord tied on but that’s about as professional as using the wee toy screwdriver to tighten the screw that caused the call-out in the first place.

 

[mikgle]

I used one for over a year before I got my Zappi, and still use it from time to time for particular reasons. However, I'm lucky enough to have a garage with its electrics on a dedicated circuit, and its power points are metal-jacketed, not the usual plastic. I have never felt the plug even faintly warm, even the times I did a full 26-hour charge from <10% to 100%. The pins on the plug are still as pristine as the day I got the car.

However, while visiting a friend with a big solar array on a FIT tariff on a sunny day, we thought we'd try swiping some free sunshine for the car. I used a purpose-made EV extension lead (my friend initially produced a puny-looking domestic extension lead, and I said, I don't think so) and we didn't charge for very long as I had to go, but in that time the plug and socket had become quite warm to the touch. There was no sign of any damage, and I've felt warmer plugs in my house from time to time (Christmas tree lights, and a fan heater), but I wouldn't have been comfortable leaving it overnight.

Yes mine gers warm after an hour or so. I think that's quite normal but I wouldn't leave it on all day or especially night.

 

[mikgle]

I used to have a nice little sideline when I serviced and repaired showers. I always carried a couple of surface and especially pull cord switches in the car. If the terminals weren’t tightened with a decent broad screw driver and the user liked a long shower some of those cheaper switches didn’t last too well.
Very, very often the customer would then point out the length of the cord - even after I’d pulled it through, re- knotted it and trimmed it off. I had instances in old castles and mansion type properties where I needed to change the cord for new, even longer ones ?. I did see old bits of cord tied on but that’s about as professional as using the wee toy screwdriver to tighten the screw that caused the call-out in the first place.

Now I'm on an export tariff I tend to only use the evse at night, leaving the solar to export. As an electrician I was intrigued by these so called EV charger sockets so I have ordered one and shall report back after I've used it a few times..

 

[GaryMG4]

I've been using the one supplied with the car for over year now. No issues with using it from the ring main, no socket scorching or excessive warmth even after a 10-100% charge. Now I'm on an overnight tariff I do a 5 hour charge overnight as and when I need it, plus a few hours to soak up any solar excess, although at present the battery is sitting at 80% so I'll let that get back to around 40% before charging again.

 

[Montego]

Like others on here, I used the granny lead that came with the car until I got a PodPoint installed a few weeks after delivery. I have also used the granny lead when on holiday and staying in holiday cottages without EV chargers. No problems. Being retired I should probably have saved the money on the Pod Point and just had an external socket fitted off a spur. It works well if you plan accordingly.

 

[mikgle]

Like others on here, I used the granny lead that came with the car until I got a PodPoint installed a few weeks after delivery. I have also used the granny lead when on holiday and staying in holiday cottages without EV chargers. No problems. Being retired I should probably have saved the money on the Pod Point and just had an external socket fitted off a spur. It works well if you plan accordingly.

Possibly but there's no doubt that a proper evse charger is safer and certainly more convenient if you need a fast or full charge.. plus there's the advantage or a cheaper off peak tariff but I;m not sure whether you would qualify with a Rolec and an MG4, do you know?

 

[Grriff]

I used a granny charger for over 10 hours continuously when on holiday, with permission from the owner. It was a modern house and no problems.
A 3kW heater takes as much current as a granny charger and the house electrics should cope with that.

 

[mikgle]

I used a granny charger for over 10 hours continuously when on holiday, with permission from the owner. It was a modern house and no problems.
A 3kW heater takes as much current as a granny charger and the house electrics should cope with that.

ev granny will take 10A usually, so only 2.3kW at the most.. its good they let you charge up tho.

 

[Rolfe]

It's not the amount of power drawn that's the issue, but rather the fact that it's continuous. The heaters usually have a thermostat and turn off and on. Mind you, some are continuous, and I have one that I think is 2.5 kw that's continuous (except it finally died after well over 50 years so I need to dump it) and it never started a fire in all that time.

 

[GaryMG4]

Possibly but there's no doubt that a proper evse charger is safer and certainly more convenient if you need a fast or full charge.. plus there's the advantage or a cheaper off peak tariff but I;m not sure whether you would qualify with a Rolec and an MG4, do you know?

I assume by 'proper' you mean 7.4kW as opposed to 2.3kW granny? Is there any evidence that a granny used correctly is any less safe? I'm on standard Go with the granny, so I can spend around £1k for a compatible Ohme or Zappi to reduce my cheap rate from 8.5p to 7p, that's an awful lot of kWh to cover that cost. If I need a fast charge then I'll pop to Sainsbury's and use their 150kW chargers and accept that I might spend £20 more than I would at home, I've done this once in 15 months of ownership.