Granny/UMC charger outdoors

[Jeeves]

Apologies in advance if this these are FAQs, I couldn't find the answers with my searches.

1. Must you take any extra steps to use the granny charger outside in case it rains?
2. What sort of power will I get out of a 3-pin plug? I'm presuming it will be very low, but how many kW is likely?

Thanks

 

[nxsynjs]

1. Notionally, the official granny charger is water resistant(but not proof). When i've used it outside i've made sure it's under the car and off the floor) I also used a weatherproof extension lead with a built in RCD 13A Splash proof extension lead (RCD options)
2. Last time I used it, it put 10a and it added 13% of charge in 4 1/2 hours (so about 2.4kw)

 

[Jason71]

if using an extension lead I recommend a a water proof box that will hold the the UMC and the plug connection such as a DriBox-DB-285. just to be safe

https://www.amazon.co.uk/DriBox-DB-285-UK-G-285-Medium-Weatherproof/dp/B01HR550I2.

 

[Jeeves]

if using an extension lead I recommend a a water proof box that will hold the the UMC and the plug connection such as a DriBox-DB-285. just to be safe

https://www.amazon.co.uk/DriBox-DB-285-UK-G-285-Medium-Weatherproof/dp/B01HR550I2.

It’s an external socket at a holiday rental that the owner has separately metered specifically to allow EV charging.

Thanks for the tip on the box. That might be a good idea anyway. I can’t help feeling that it might be unsafe to leave the UMC naked in the rain, but I know little about electricity, I’m just scared of it.

 

[nxsynjs]

It’s an external socket at a holiday rental that the owner has separately metered specifically to allow EV charging.

Thanks for the tip on the box. That might be a good idea anyway. I can’t help feeling that it might be unsafe to leave the UMC naked in the rain, but I know little about electricity, I’m just scared of it.

As mentioned above. put it under the car, off the ground and with a weather proof lead and RCD cable connected. It'll need to be a serious abandon ship flood to submerge it, and in the unlikely event it does the RCD will trip before doing any real damage.

 

[Arran]

It’s an external socket at a holiday rental that the owner has separately metered specifically to allow EV charging.

Thanks for the tip on the box. That might be a good idea anyway. I can’t help feeling that it might be unsafe to leave the UMC naked in the rain, but I know little about electricity, I’m just scared of it.

I've been charging off a Granny lead and extension cord down the garden for the last 6 months. Just had the extension end and the UMC in a Dri-Box as stated above. You will need to get some pliers on the cable exit from the box as the UMC/Type 2 cable is quite a bit thicker than the holes already in the box.

It's worked flawlessly for me, not a drop has gotten inside!

 

[Peter 224]

3kw from a granny charger and although the Tesla car socket is waterproof, the 13A plug at the other end of the cable is not, so don't get it wet....

 

[Adopado]

3kw from a granny charger and although the Tesla car socket is waterproof, the 13A plug at the other end of the cable is not, so don't get it wet....

Despite the 13amp plug you don't get 13amps you get 10 amps ... so depending on your voltage that will be 2.3 to 2.4 kW. It's an intentional de-rating. Though we have 13amp sockets they are not commonly used for running at their full rated output for 12 hours at a time so it just saves overheating problems.

 

[Avendit]

You should be fine if your destination has been set up specifically with EV's in mind, but the charger can expose any weaknesses in a wiring circuit. I keep checking it every while for the first charge, either through the app or just touching the plugs to check they aren't heating up. Room temperature is fine, any more and there is a problem.

I've pulled entire charges over the course of a weekend via an extension and the granny charger. Completely fine, just slow.

 

[Jeeves]

Thanks for your helpful replies everyone.

 

[adsheff]

I use the granny charger at my parents' house. Roughly puts in 3% an hour which is slow but fine if you're there for the weekend!

 

[MrBadger]

Our regular charging is at 10A on Octopus Go 4 hour tariff. On our LR, I bump the charge limit by 11% and 99% of the time, we get the full 11% within the 4 hour window - we could obviously charge longer, but several 11% charges are sufficient for our current weekly needs. This time of year, 10% gets us about 27 miles of driving our regular trip, in cooler temperatures (~5C) the same trip takes around 13%. We might lose a little bit more if we pre-condition.

 

[Avendit]

a 16A socket taunts you thus:

The 10A granny is fine on occasion, but not sure I could keep the self control you are showing outside of special occasions! Moving up to 16A for home charging was pretty reasonable, as you could do a pretty big charge in 1 night if needed, finally having my 'proper' anderson is just a nice luxury really.

 

[Jason71]

I use the granny charger at my parents' house. Roughly puts in 3% an hour which is slow but fine if you're there for the weekend!

If you are getting 3% per hour then I am assuming you own an M3 LR or P then.

 

[Adopado]

If you are getting 3% per hour then I am assuming you own an M3 LR or P then.

Quite… when percentages are quoted it’s worth mentioning the car battery size… clearly 3% of an SR+ battery is a very different quantity to 3% of a 100D battery!

 

[toshman]

a 16A socket taunts you thus:
View attachment 663371

The 10A granny is fine on occasion, but not sure I could keep the self control you are showing outside of special occasions! Moving up to 16A for home charging was pretty reasonable, as you could do a pretty big charge in 1 night if needed, finally having my 'proper' anderson is just a nice luxury really.

Where can I get a socket like that?

 

[Avendit]

Where can I get a socket like that?

Ah well, now you are going off topic...

Short answer is Screwfix or similar, longer answer is 'if you are installing it as a permanent car charge point then it has to be protected as signed off as such'. In which case it's going to cost you 70%+ of getting a proper charger installed.

I ran one for 18 months which I installed off my garage feed, but it was 'temporary' and I knew it was so, treated it nicely.

You also need the right connector from Tesla, but that is just a phone call away.

 

[Adopado]

Where can I get a socket like that?

As you appear to be in Canada I don’t think there’s anyone in the uk/Ireland forum able to answer that! Tesla’s website should show what the UMC connector options are for your area.

 

[Avendit]

As you appear to be in Canada I don’t think there’s anyone in the uk/Ireland forum able to answer that! Tesla’s website should show what the UMC connector options are for your area.

DOH! Totally missed that! Canada should have equivalent 240v 16a+ solutions that an electrician can fit. The US does...