UMC charging only

[Basicbob]

Hi,

Long story but I cant get a proper charger installed.

My plan is to use the plug socket in the porch and charge the car that way. I have a small bounce glazed porch window I has hoping to charge it only during the day while I’m at home. There isn’t a security issue as the main door is upvc double glazed and I also have a heavy oat door with a yale security lock.

I know it’s a bit rubbish but I will only be doing 100 miles a week

anyone else just relying on the umc only?

I could get an outside socket installed relatively cheap as the 3 pin socket is inside the porch.

 

[R5scott]

I have a similar set up and have been doing the same for several months. Works well but I do plan to install a charger in due course. i have an outside socket but it is on its own circuit with good protection.

What I try to do is make use of cheap/free destination charging as much as I can to keep things topped up! What you will notice is that all those short little journeys add up to more than you think!

The downside of you charging in the day will be that you wont be able to benefit from off peak tariffs. Not the end of the world though.

What I don't know is whether a UMC or home charger is better for battery health, or if there is really any difference.

 

[LongRanger]

If you could get a 16A commando socket installed with proper protection on the consumer unit that would be good enough for 90% of the time. Then buy the 16A UMC connector.

Gewiss or ESR make decent interlocked IP rated commando (CEE) type switched sockets.

On the LR battery, if I use my 16A commando location I can reliably expect 50% of charge in about 10 hours. So 20-70% or 30-80 etc.

Makes sense to have a waterproof box outside for the UMC unit as over time I don’t think being in heavy rain/dust will be the best thing for the unit or the interchangeable power connectors - but even something like a simple meter box would do the job. Depends how far you want to go.

If stuck with the 10A option (13A 3-pin plug) then from memory I think it’s 7 miles per hour max gain, so something like 15 or 16 hours for 50% charge increase. Not completely unusable if your weekly mileage is low.

Again from memory I think you want to be keeping the minimum battery level above 20% where possible - so work out a routine where this works for you, not fighting against you all the time ....

 

[Glan gluaisne]

Charging using the UMC is fine, only real downsides are the slightly poorer charging efficiency and the longer charging times. The slightly poorer charging efficiency means the running cost will be slightly higher, but in all honesty, given all the other variables, like the weather, it's probably down in the noise.

As far as battery health is concerned I doubt it makes a jot of difference. The battery management system takes care of things pretty well, and cell balancing (when needed) during charging only happens when the battery is being charged from the onboard AC charger(s), so all should be fine.

If you get an outside outlet installed, then best to try and see if you can get a 16 A interlocked commando, rather than a standard 13 A outlet, as that will allow charging at 16 A, with the UMC commando adapter, rather than just 10 A with the 13 A adapter. Any outlet for charging an EV needs to be protected by a DC tolerant RCD (a Type B or Type EV), and if the house has a TN-C-S/PME supply the outlet also needs some form of open PEN protection (earth rod's the cheapest/simplest, usually).

 

[phil4]

I've been using the 3pin UMC since I got the car, and have no arrangements yet to get a proper charger installed.

As mentioned above it only runs at 10A, so about 6/7mph. My normal daily commute is 40 miles roundtrip, so easily enough to get that over night every night. I'll be needing something else for longer trips but that's what superchargers and the like are for.

In terms of where it's plugged in, I've got a mains plug right by the garage door, so the cable goes under the door and into that, leaving the tesla block in the garage, and only the lead and plug outside.

I will get a proper charger, but with the covid "work from home if you can", I've not done, and have no real plans to do more frequent further distances just yet.

 

[M3noob]

You'll be fine. Don't over-think it As phil4 said, Superchargers are there for longer trips and fast recharging.

Octopus Go is recommended. I have a referral code if you'd like to save some money

 

[Basicbob]

Cool.

I think I’ll be sticking with the UMC 3 pin plug.

the main unit Will be inside the porch so always protected and I can then feed the other end through the small porch window.

The new range is 267 but is this on the assumption you don’t use the first and last 20% or is the range the full 100% to 0 which is not good for the battery?

is the minimum setting 20% to 80% or 20% to 90%?

thanks

 

[LongRanger]

In the app on your phone you can select charge limit % accurately in increments of 1% - so plenty of opportunity to go to 79, 91 or anything in between.

Mostly folks seem to be happiest at limiting to 80% for maximum battery protection but you can vary this 80-90 would seem fine to me, I am not fussed if the car degrades by a few percent in its lifetime with me.

 

[Avendit]

Again, don't over think it. Your range suggests an SR+? and will be for 100%-0%. Hitting the top and bottom of that is fine, but don't do it every night. Use it when you need it and otherwise charge to 85(paranoid) or 90%(official recommendation).

The car gets a lot more meh under about 20% so you wouldn't be setting out at that, but it's fine to finish a journey.

The car takes about 2A to run its systems while charging, which is 20% of the input for the length of time it takes to charge (best part of 24 hours for me last night or arriving on holiday). At 16 amps you still lose the 2A, but only for 14 hours in this example. Feels more efficient, but meh, it all works. Only real difference is if you need a quick turnaround one night, which might mean an extra charger stop the next day instead.

Use it, charge it, try not to worry too much about all the battery management stuff. The car will tell you if it thinks you are abusing your investment!

 

[Sparkeur]

I've used the UMC since getting delivery of my M3LR in May. Although I live mainly in France, I don't think there's that much difference between the UK at a charging level. Until last week, I've been using the basic domestic supply on night tariffs. I start most days at 80% and finish normally at 60%. Using the basic plug, this took about 5/6 hours to top up and cost about 2.30€. I now have what I think in the UK is called a commando plug, which is a 32A supply. I've used it twice since installation and the charging time is about 2.5hrs which is excellent for me. I really only upgraded because on rare occasions, I will travel more in the morning - down to about 40% - and I need a day charge so I'm OK for the evening. The only other charging I do is for destination driving and that's down to the Tesla network. I doubt very much whether I will bother with a wall charger.

 

[thrash]

I've been using the 3 pin since I took delivery about a month ago. I've only used it a handful of times, usually going from 50/60% back up to 80% - if left overnight it's perfectly fine for current circumstances and I could've got away with using it a lot less.
I'm waiting for my wall charger to be installed (and to be switched from Octopus standard tariff to Go) and I'm only really getting one because I think it will be useful when back to working in the office and making more regular journeys. But the 3 pin has been doing the job fine with no issues at all so far.