Granny charger safety

Jonperry64

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We should be getting our car on Tuesday (it was supposed to be today but that's another story) and Octopus have yet to give me a date for installation of a charger. I had intended to use a granny charger in the meantime. However, our house is 35m from the car so I'd have to use an extension lead. There was a discussion about granny charging on the MG4 Facebook group in which people said granny charging was inherently unsafe and a fire hazard - even without an extension lead!
What are your views on this? Also, is it possible to limit the current drawn to say 1kw,so as to mitigate the risk?
 
It isn't inherently unsafe. I have used it for 3 years without issue but it is from a cerified EV charger plug.

Extension leads aren't ideal but as you say you can turn down the current to mitigate the risk. The car can do 6A or 8A even 8A steps down any risk considerably. Keep in mind that the car resets the charge current back to 'AC Current' each time you drive it so you'll have to remember to select it each time. Better if you can do that on the granny charger.
 
My Aussie granny charger doesn’t do much more than 1.5 kW anyway, but when I use it (which is not often) I use an extension cord. A few people on here use extension cords but I believe you need to make sure the internal wires are at least 2,5mm². Someone will be along shortly to correct me if I’m wrong.

Thread 'Charging from a granny lead, dangers???'
Charging from a granny lead, dangers???

You might find some more info here as well
 
As said above, it's not inherently unsafe. You just need to think about volt drop and the physical protection of your cable.
 
Thanks both. Is the draw determined by the lead then, or can you set it in the car? Sorry, I don't understand the bit about the car resetting to AC current. I thought a granny lead from the house would be using AC current so I wouldn't need to change AC/DC setting in the car would I?
 
I would be making sure the extension lead is fully unwound and that any sockets/plugs are under cover to prevent water coming into contact. My granny charger uses less energy than my electric kettle. They are perfectly safe - if you have any doubts about your electricity supply, get in an electrician to check - I did. He found the earth on the socket in the garage I was using faulty and he upgraded the RCD.
Hope this helps
 
It sounds like you are hopefully only going to use the 'granny' EVSE until your 7kW unit it fitted. Just get a good quality extension cable rated at a continuous 13A and the length you require. It is justcas important to make sure the socket you use is in good condition. Regularly check for heat at all the plug and socket connections. I used a granny for a couple of months until my 7kW Zappi was fitted.
 
I would be making sure the extension lead is fully unwound and that any sockets/plugs are under cover to prevent water coming into contact. My granny charger uses less energy than my electric kettle. They are perfectly safe - if you have any doubts about your electricity supply, get in an electrician to check - I did. He found the earth on the socket in the garage I was using faulty and he upgraded the RCD.
Hope this helps
Also make sure the extension lead is rated 13amp, some are only 10amp. You should be able to find most places but a good place to go is 13A Extension leads
 
The key to charging safely with a Granny charger is in the quality of the 240V 13A components.
BS 1363-2 products are rated for continuous EV charging (10A max). The MG Granny charger is rated at 10A, or if you are buying one make sure it is the same, or switchable 6, 8, 10A. Some chargers try to charge at 13A claiming it is faster, which it is but not suitable for the UK.
As for extension leads, again not unsafe but you do need a good quality bespoke one such as the ones available from Industrial Extension Leads.co.uk or Toughleads.co.uk. Links below to some of their products
Industrial Extension Leads
Toughleads.co.uk
 
Thanks both. Is the draw determined by the lead then, or can you set it in the car? Sorry, I don't understand the bit about the car resetting to AC current. I thought a granny lead from the house would be using AC current so I wouldn't need to change AC/DC setting in the car would I?
If you have a look at the charge page in the infotainment system (click on the tile on the main page) you’ll see an option somewhere in the lower left quadrant that lets you tell the car what amperage you want to use. This specific setting will reset to 32A.
 
We have no choice but to use an extension cord with the charger. 2.5mm sq conductor cable min., 35 mtrs is a very long extension cord, so, if you can find a cable with 3mm sq conductors, that would be better.
Don't expect the charging to be too fast, the voltage drop over that distance will be quite a bit.
In the charging screen in the car, you can select different amps, I'd go with the lowest, just to be safe

T1 Terry
 
We have no choice but to use an extension cord with the charger. 2.5mm sq conductor cable min., 35 mtrs is a very long extension cord, so, if you can find a cable with 3mm sq conductors, that would be better.
Don't expect the charging to be too fast, the voltage drop over that distance will be quite a bit.
In the charging screen in the car, you can select different amps, I'd go with the lowest, just to be safe

T1 Terry
If OP wants the correct cables for the job then toughleads.co.uk they aren't cheap and maybe too much for a few weeks.
 
Could you not save on the cost of an extension cable and use a nearby rapid charger until your home charger is installed. Understand the cost per Kw is more and you do not have an install date yet. Also, if you are on the standard tarrif with Octopus you cannot benefit from the cheaper rate. If you are on one of the Go tarrifs you will also need a timer which the car may/may not have.
 
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