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Ideal or Cost Effective Home Charging

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I work from home (mostly), so weekday driving won't be an issue. It's the occasional longer trips that might be done on back to back days that might be an issue. But really, the issue part of this is whether I may need to schedule a grid draw or perhaps a charge somewhere else. Not the end of the world.

The next thing to work out is whether I should go Zappi 3ph, or use the Tesla Wall Charger + Charge HQ - I think the latter should work fine to soak up the excess solar correctly, but I'm not sure yet. I want to leave the UMC in the car all the time and not use it at home (as in take it in/out all the time). We own our home, so setting up a permanent charging setup is not a big deal (right next to the powerwall :) ).
Someone else may have more info on this, but I think tesla are soon to make their gen 3 and powerwall talk tomeach other to send excess solar to the car. If this occurs it should be a very tidy solution
 
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I have the following charging options closer to my place.

what additional adapters do I require to charge my upcoming M3?

CCS/SAE 1 Plug 50 kW 1 Station

CHAdeMO

Chargefox Type 2

J-1772

Also, if I go with 32A 3phase industrial-type socket and wire it for single phase + Gen2 Adaptor 32A 5pin - Do i need to buy a Tesla wall connector?

thanks
 
Just picked up a 2022 model 3 and am now looking at faster than 10a home charging options with the UMC. I have 3 phase power at home.

I've read the whole thread and the very useful pdf guide that someone posted previously by Rudi Cheow. I just want to confirm my understanding of what I need for home 32a charging.

- 5 pin 32a socket connected to 3 phase power
- 5 pin UMC tail. It runs at 32a because only one of the three pins is wired

Is that correct?
 
I have the following charging options closer to my place.

what additional adapters do I require to charge my upcoming M3?

CCS/SAE 1 Plug 50 kW 1 Station

CHAdeMO

Chargefox Type 2

J-1772

Also, if I go with 32A 3phase industrial-type socket and wire it for single phase + Gen2 Adaptor 32A 5pin - Do i need to buy a Tesla wall connector?

thanks
You will need a specific adapter for all of your “close to” charging options, and eventually options 1 and 4 will be changed to CCS2 and type 2 as that is the standard supported mr the MTA.
If you install a 32A 3 phase socket you can use your UMC with appropriate adapter.
If it were me, I would buy a Type 2 to Type 2 cable for the ChargeFox Type 2 and a wall connector as it saves having to remove and repack your UMC every time you charge at home.
 
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Just picked up a 2022 model 3 and am now looking at faster than 10a home charging options with the UMC. I have 3 phase power at home.

I've read the whole thread and the very useful pdf guide that someone posted previously by Rudi Cheow. I just want to confirm my understanding of what I need for home 32a charging.

- 5 pin 32a socket connected to 3 phase power
- 5 pin UMC tail. It runs at 32a because only one of the three pins is wired

Is that correct?
Yes, you will get approximately 7.4Kw charging with that combination.
 
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You will need a specific adapter for all of your “close to” charging options, and eventually options 1 and 4 will be changed to CCS2 and type 2 as that is the standard supported mr the MTA.
If you install a 32A 3 phase socket you can use your UMC with appropriate adapter.
If it were me, I would buy a Type 2 to Type 2 cable for the ChargeFox Type 2 and a wall connector as it saves having to remove and repack your UMC every time you charge at home.
do you mean tesla wall connector?
 
Ok, that was quite helpful. I think it's going to be the Tesla charger and since I can code as well, perhaps I need to look into how easy it is to access the relevant api(s). Could be a fun little project.
Have you had a look at the Home Assistant addon? Might be something to use as a starting point if you want to code your own solution. And if you do, it would be great if you could share it with the community. Optimizing use of unused Solar Power to charge a Tesla
 
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what additional adapters do I require to charge my upcoming M3?
All the CCS chargers in Adelaide are CCS 2 and will plug straight into your Tesla
There are no adapters for Chademo for Tesla Model 3, and any charging station with one will have a CCS 2 plug as well
There are a lot of type 2 chargers in Adelaide and it may be worth buying a type 2 to type 2 cable if you are normally going to where they are for other reasons on a regular basis and they are free, but at $250 you need to get in the region of a MWh of power from them just to break even

Also, if I go with 32A 3phase industrial-type socket and wire it for single phase + Gen2 Adaptor 32A 5pin - Do i need to buy a Tesla wall connector?
No, a Tesla wall connector will give the same maximium output on single phase as the UMC, and cost you $780
 
The two most expensive options, and why would you need to remove and repack your UMC every time you charge at home
If you choose to use the UMC that’s fine, but it’s not designed to mount to a wall, and has no cable management, so to some degree it is at risk of being run over or causing a trip hazard in the garage. the wall connector is not perfect, but it’s a lot better.
The Tesla wall connector is pretty good value when compared to the fixed alternatives and I consider that an investment in the house infrastructure to support my current and possibly future EV.
Technically, like a spare tyre, the UMC is part of the car and is sold with it. Certainly if I were buying second hand one of my checks would be that the car came with the UMC, so you are back at square 1 with your next EV.
Similarly, the Type 2 to Type 2 is an investment in infrastructure for your EV as a number of type 2 chargers are without cables And can be used with your next EV.
I didn’t recommend buying J1772 or CHADEMO adapters as those Standards may not be around for ever.
 
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why would you need to remove and repack your UMC every time you charge at home

I have the HPWC in my garage and the UMC stays in the car at all times in case I ever need to use it, and it‘s very convenient to not have to pack it.

I have used the UMC on the road a few times when staying at holiday houses in rural areas not close to public chargers. Park the car close to the house and run the cable out to the car for overnight charging.

Trips and plans can change without notice, and if you use the UMC at home at all times, the one time you can’t be bothered to pack it when you go on a trip is almost guaranteed to be the one time you really wished you did.

My HPWC did come with the car, though.
 
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I have 3 phase power at home.
I just want to confirm my understanding of what I need for home 32a charging.

- 5 pin 32a socket connected to 3 phase power
- 5 pin UMC tail. It runs at 32a because only one of the three pins is wired

Is that correct?
Yes.
I suggest running 5x6mm² 3phase wiring to the socket and wiring it as 3phase.
When charging via the 5pin UMC tail you'd only get 7kW, however in the future should you invest in a 11kW or 22kW 3phase Wall box or portable charger then you'd be able to charge at 11kW for Model 3 (or 22kW).
 
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How long does it take to charge via solar alone?
How long is a piece of string?

Better to look at the charge speed based on charge current. As you have a Powerwall already, you can easily see from the app how much "excess" solar you have at various points in the day.

For charging from solar, in my opinion a charger that can go up to 32A single phase is better than up to 16A 3 phase. While 16A 3 phase will let you go to 11kW, you can only adjust in 1A increments which is 720W increments, so more fiddling.

With single phase 32A (for example the UMC with a 32A tail) you can go from 1.2kW to 7.68kW in 0.24kW increments.

So, 1.2kW will add around 7km each hour of charging. 7.68kW will add around 45km/h.
 
Just be wary of charging at very low currents. Both my EVs are only 50% efficient at 6A (single phase) so that can be very wasteful. I charge direct from solar if my excess is >= 10amps and if excess solar <10A, it goes into a battery (at over 95% efficiency) and I pull it out for the EVs at 95% efficiency and around 14-16amps.
 
Just be wary of charging at very low currents. Both my EVs are only 50% efficient at 6A (single phase) so that can be very wasteful. I charge direct from solar if my excess is >= 10amps and if excess solar <10A, it goes into a battery (at over 95% efficiency) and I pull it out for the EVs at 95% efficiency and around 14-16amps.
Please explain...

If I charge at 5A (single phase), I get ~7km/h. If I charge at 10A (single phase), I get around 14km/h. At 20A, it's ~28km/h. I can't seen any inefficiencies here at all.
 
I am measuring kW into the car and comparing with kW into the battery using Scan My Tesla. 6amps and 230V. Aircon, radio and lights all off. 54% is what I get. Zoe can be worse in hot weather when the cooling fan runs. I ran these tests a couple of months ago.

I get 96% efficiency at 14amps which is excellent.

It is possible that PF (Power Factor) plays a role.

As a totally separate matter of interest, JOLT (supposed to be 25kW) is rather inefficient because of battery heating & coolant pumps, particularly in an LR or P. These figures from yesterday

23.0 min charge duration
5.65 kWh added to battery
8.06 kWh gross recorded by both JOLT and SMT (within 0.2).
70% efficiency. Most waste (at over 6kW) went into heating the motor stators to heat the battery to 45degC.

If you can get 100% efficiency charging at 6A, then go for it. I do not and therefore avoid it. I have not bothered to see why (coolant pumps, DC-DC converter et al). I just avoid low amp AC charging. YMMV.
 
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