3 Phase Upgrade

[Nick W]

When I knew that I was getting an MG5, I phoned the DNO to ask them to check the service fuse rating. They said that as part of their commitment to low carbon technologies, if the maximum demand was greater than the limit for single phase, they would upgrade the supply to 3 phase.

It was a significantly larger project than I or my neighbours were expecting but was done very professionally. The hardest part was getting hold of a SMETS2 3 phase meter - they are rarer than the proverbial!

 

[Jomarkh]

Wow. I wouldn't have room under the stairs for all that three phase kit.

 

[rogerco]

"DNO" - wozat?

Did you have to pay for it at all?

So does this mean you can charge using a CCS connector? I understood that the MG5 could only use one phase of a 22kW type 2 connector so you would only get 7kW.

What domestic CCS chargers are available?

Or was your supply too weedy to even add a 7kW charger to start with? (presumably you don't have an electric cooker or shower then)

 

[Nick W]

"DNO" - wozat?

Did you have to pay for it at all?

So does this mean you can charge using a CCS connector? I understood that the MG5 could only use one phase of a 22kW type 2 connector so you would only get 7kW.

What domestic CCS chargers are available?

Or was your supply too weedy to even add a 7kW charger to start with? (presumably you don't have an electric cooker or shower then)

Distribution Network Operator - the company which owns the distribution network. And who paid!

Theoretically I could install a CCS charger but they are Megabucks. I am going for a 3 phase zappi as although the MG5 can only use one phase (the L2 and L3 pins aren't even present in the socket) more cars will accept 3 phase even if only at 11KW.

It was because I had a 10.5KW shower and an electric cooker that another 7KW would take me over 100A. 240A gives plenty of headroom and scope for heat pumps in the future.

 

[rogerco]

Thanks. One of the reported features of the new 2021 (or 2022 in UK) MG5 is three phase/22kW charging. I guess the reason we only have 7kW is to keep the price down so it might be possible to retrofit the two missing charge controllers and get 22kW.
Not sure exactly how Li chargers work, whether they are pulsed or constant current. Can one simply parallel connect the DC output of three single phase chargers to increase the max rate I wonder.

Having said which I went for the single phase Zappi and the kids will have to put up with only 7kW when they visit (there's a Zoe and an ID3 already in the family)

 

[Nick W]

Not sure exactly how Li chargers work, whether they are pulsed or constant current. Can one simply parallel connect the DC output of three single phase chargers to increase the max rate I wonder.

No - a three phase bridge rectifier uses the 400V between phases rather than 230V phase to neutral, and the higher power from the smoother rectified waveform. And even if you could link the phase terminals, you'd still need 96A with 100A being the DNO limit for a single phase supply.

 

[rogerco]

Ah, I see. Clearly a three phase zappi (or whatever) will need a 3 phase supply - but you managed to get one put in for free (incidentally which DNO? ours is Western Power, but I guess Northants is not going to be them)

I thought that the Type 2 connector simply delivered AC and the CCS varient used the 2 extra big beefy pins to deliver DC. So the existing 7kW internal car charge controller should be able to be replaced with a 22kW one and a replacement socket with the other two pins connected to pick up the other phases. All the wall charger has to do is current limit the feed to the car in a more or less intelligent way?

Quite how the in-car charger converts and distributes 240 (or 400) volt AC to the cells as DC (or pulsed DC) I have no idea. I thought I had seen an outline schematic somewhere that simply showed a 22kW capable vehicle as having three separate identical charge controllers each connected to a single phase so that the same components (or one of them) would work if connected to only a single phase (as delivered by my single phase Zappi.)

If this is the case the modification to the car might be relatively simple...

 

[Nick W]

Ah, I see. Clearly a three phase zappi (or whatever) will need a 3 phase supply - but you managed to get one put in for free (incidentally which DNO? ours is Western Power, but I guess Northants is not going to be them)

I thought that the Type 2 connector simply delivered AC and the CCS varient used the 2 extra big beefy pins to deliver DC. So the existing 7kW internal car charge controller should be able to be replaced with a 22kW one and a replacement socket with the other two pins connected to pick up the other phases. All the wall charger has to do is current limit the feed to the car in a more or less intelligent way?

Quite how the in-car charger converts and distributes 240 (or 400) volt AC to the cells as DC (or pulsed DC) I have no idea. I thought I had seen an outline schematic somewhere that simply showed a 22kW capable vehicle as having three separate identical charge controllers each connected to a single phase so that the same components (or one of them) would work if connected to only a single phase (as delivered by my single phase Zappi.)

If this is the case the modification to the car might be relatively simple...

Western Power here too - they cover a big swath of the country.

 

[Jonhklee]

I’m still waiting for a SMETS2 3 phase meter for my 2 phase supply. My 1900 house has 2 phase supply already, so I can use dual phase IN and two single phase out - totalling 120A single phase supply. So glad there will be no digging up the front yard!

 

[ARealHuman]

Looks like a tidy job I like how the bloke on the grab lorry has his hard hat on, but the two on the ground where the risk of getting hit by the grab is bigger, don't! I'll get me coat....