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Discussion Starter #1 (Edited)
Please note trying this at home may invalidate your warranty and is not recommended.


I Finally got round to sending another Phase to the car, couldn't get to L2 connection in the wall box without stripping the
Finally got round to send another Phase to the car, could get to L2 connection in the wall box without stripping the whole thing down so connected up L3.

What do you know car has been charging at 7Kw for an hour now. Neutral cable is a little warm in the engine bay but nothing to worry about, That makes a recharge time of 4 Hours from completely flat.

That does make the car much more useful.
Finally got round to send another Phase to the car, could get to L2 connection in the wall box without stripping the whole thing down so connected up L3.

What do you know car has been charging at 7Kw for an hour now. Neutral cable is a little warm in the engine bay but nothing to worry about, That makes a recharge time of 4 Hours from completely flat.

That does make the car much more useful.
thing down so connected up L3 to the relay in the wall box.
Plugged the car in using the supplied 3 phase cable, What do you know car has been charging at 7Kw for an hour now. That makes a recharge time of 4 Hours from completely flat. 78-100% in 1Hour

That does make the car much more useful.

See attached Photos
 

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thinking about it, theres a danger of overloading things if its a public point.

If the charge point were labelled up as 7kw, but were to signal only 16A on its CP (perhaps for instance the 7kw is shared between two sockets), then the car should only draw 16A. However with this hack, both chargers will draw 16A.

What you'd really want is some widget that detects the charge point signalling "32A" and then switches in a relay or something to pull the extra phase in.

Even more clever, you'd want something that processed the incoming allowed current and adjusted the output CP accordingly. IE if the charge point signalled "25A" then you'd want it to switch both chargers in, but limit them to 12A (or 12.5) by signalling "12A" to the car
 

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Ok....! this is confusing me. so your getting a 7kw charge from single phase at home? where did you Mod on the car or the charger? Have you got pictures? Im getting 7kw from a three phase Ac charger local to me.
 

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Its linked to another discussion that was ongoing in here a while back.

Essentially the car has three seperate isolated 3kw chargers. In the UK and europe these are connected one per phase to the 3 phase inlet socket.

In the USA, where three phase electricity isnt very common, the three chargers are ganged together and ran from a single phase.

It was suggested that by simply connecting the existing single phase supply, to an additional phase terminal in the EV, should fire up that additional charger.

Obviously the control signals are different, as the US cars can request upto 48 amps from the wallbox, and the wallbox will output the correct current limiting signal as required if for instance it can only manage 32A. Which is what i mentioned in my post above.
 

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Its linked to another discussion that was ongoing in here a while back.

Essentially the car has three seperate isolated 3kw chargers. In the UK and europe these are connected one per phase to the 3 phase inlet socket.

In the USA, where three phase electricity isnt very common, the three chargers are ganged together and ran from a single phase.

It was suggested that by simply connecting the existing single phase supply, to an additional phase terminal in the EV, should fire up that additional charger.

Obviously the control signals are different, as the US cars can request upto 48 amps from the wallbox, and the wallbox will output the correct current limiting signal as required if for instance it can only manage 32A. Which is what i mentioned in my post above.
Thanks but my questions was aimed at Richiec, because he as repeated his text a few times its hard to understand.

I know it has three chargers and kinda understand how it works but trying to get my head around how he got 7kw from a uk home charger which outputs 3.6kw. I can get 7kw from a uk 3phase but would like to get that from my home charger.
 

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Discussion Starter #8
So I have a 32a (7kw) home charger (wall box). I have been charging my car using it at 16a (3.6kw) for the last 18months. I removed the cover from the wall box and where the power comes out of the relay I connected an additional cable and terminated it in the L3 terminal of the change socket.

I then connected the 3 phase cable supplied with the car. This sent 230volts down the cable to the cat on the L1 and L3 cables (to send power down the L2 cable would require a complete strip down of the wall box).

The car started to charge, checking the app it showed a standard single phase 16a charge time, but the car (see pictures) used 32a and charged in half the time.

I hope that explains it a bit better.

Rich
 

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Nice hack @Richiec when you get the chance would you mind posting a pic of inside your charge point. I have a Rolec with tethered lead but should be easy to locate the L3 terminal I hope ☺
(Zoe is going back next week and Merc hopefully replacing it !)
 

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If you bridge phases on your cable and plug it into a public charge post that is actually three phase then at best you'll trip it out and at worst you'll have 415V across the phases in a short circuit and start a fire. Make sure the upstream direction is isolated so only connected to L1, with no connection to the pins for L2 and L3.
 

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Discussion Starter #12
Wouldn't dream of Bridging the phases. But removing the L2 cable from the L2 terminal on the plug and putting it in the L1 terminal so on a 7kw post he car will charge at 7kw. Worst thing that will happen is if it is a 3.6 or 11kw post is trip out. If it is an 11kw post I would use my standard cable and charge in 3 hours. If Its a 3.6 unless I'm there for a couple of hours it's not worth bothering with.

The idea of the cable mod is so that I don't need to hack the wall box making it ok for everyone else to use.

I'll post some pictures later today. Cable should arrive today also and I'll post pictures of the mod to but that will be tomorrow.
 

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I would say that using any modified cable on public chargers is inconsiderate, potentially dangerous and might open you to unexpected consequences. Doing it on your home charger is down to you, but obviously if it goes on fire then your insurance isn't going to pay out.

If you end up destroying a public charging post then you're going to be financially responsible for the damage, and you'll be inconveniencing other users while the charge point is unavailable.

If you're disappointed with the charge rate of your car then you've chosen the wrong car.
 

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But if like me and most the guys
I would say that using any modified cable on public chargers is inconsiderate, potentially dangerous and might open you to unexpected consequences. Doing it on your home charger is down to you, but obviously if it goes on fire then your insurance isn't going to pay out.

If you end up destroying a public charging post then you're going to be financially responsible for the damage, and you'll be inconveniencing other users while the charge point is unavailable.

If you're disappointed with the charge rate of your car then you've chosen the wrong car.
But if like me and most the guys ive spoken to Mercedes did and still are bending the truth regarding charging. So if I can do this at home like richie as stated he is doing and not at a public charging point then whats the issue? We all know thye risk and take this as a given. As the car can actually charge at 7kw and 11kw I just dont get why they will not just let us charge at 7kw at home if it can!..

So for me if I can do it and richie way will work thumbs up from me.
 

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Wouldn't dream of Bridging the phases.

The idea of the cable mod is so that I don't need to hack the wall box making it ok for everyone else to use.
Ah, I see now. And not for public charger use, though I'm sure some one will try it at some point. Not sure I'd sleep at night knowing my car might be charging at double it's designed neutral current capacity though.
 
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