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OK folks, can someone smart help me out here?

I've read a fair bit but still unsure as to what the pros and cons of each are.

Ignoring infrastructure (which in 'real life' wouldn't be smart I know) it seems that CCS is the "best" option. Better socket compatibility, smarter communications, just as fast (maybe faster in future) DC charging?

If CHAdeMO hadn't been there first (in particular on the highly successful LEAF) I wonder, what would be the arguments for it vs CCS. Or what is the argument now for CCS over CHAdeMO (ignoring profiteering and political reasons)?
 

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If CHAdeMO had been designed under the same conditions they would have likely had something like CCS, they are a smart set of engineers after all. The reality is, they had a requirement to charge a EV with DC, so they used the tools they already had, CAN bus connectors - existing connector prototypes etc. Other things given they weren't entirely certain it would take off, and to keep costs down keep as much of the complexity as possible in the plug and unit.
 

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All of the important parts of both standards are the same - you plug in a large-ish connector which has big pins that take DC directly to the battery pack (through a contactor) and smaller pins that talk between computers at each end. The car requests a certain profile of charging and the charger supplies this on the DC pins. The differences are in the specifics of the plug design, the format that the communication takes place in and the licensing and accreditation of the system and its parts.

The plug design of the original CHAdeMO connectors was the sort of thing that a specially trained operator might be fine using, but Joe Average will struggle and his 80-year old granny will probably be incapable of handling. The newer plugs are much, much better, but they are still hefty items. The CCS plug is much lighter and even easier to use than the new CHAdeMO plugs. It is not as robust though so there are issues that may be due to plugs not fitting as well (although I am not 100% sure this is the case. Also, CCS shares the same connector as the AC charging so you only need a single socket and either a much smaller flap or just one rather than two.

The details of the protocols are closely guarded, but neither is rocket-science. If you can read the specs and understand them you should be able to make this part work and as far as I can tell there is no significant advantage one way or the other. Unfortunately the people implementing these parts are not doing a stellar job!

Possibly the most important part is the licensing - it seems that you need to pay through the nose to buy accredited CHAdeMO connectors (over £1000 for a plug!), but the CCS ones are apparently much cheaper. If both were starting to be rolled out at the same time this would make CCS a simple choice.
 

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I would agree with @mgboyes.

Not sure there is really any difference between CCS and CHAdeMO. Both are fairly simple protocols with badly designed plugs and sockets (CHAdeMO is large and the early ones hard to operate; CCS has a tendency to fall out). The implementation is a bit different but I don't know whether I'd say CANbus signalling is worse than the way CCS does it (after all, CANbus is good enough for the other systems in your car).

Also as mgboyes says, at least CHAdeMO is a guaranteed standard. Whereas CCS seems to be a "non standard standard" where each manufacturer has put their own spin on it in terms of tolerances and mounting of the sockets (hence the "i3 Dance" to get the socket to lock).

The way I think it will likely pan out is that CCS will slowly come to dominate in Europe as the CHAdeMO consortium will refuse to remove its licence fee. Meanwhile Japan and probably the rest of Asia will keep CHAdeMO as they already have a huge incumbent base and the licence fees flow back to mostly Japanese manufacturers; the USA will end up with Tesla variants.

Just my guess.
 

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I think it was @Jack who coined the phrase, some time ago. Something to do with needing to get out, connect and hold the lead while you lock the doors in order to lock the plug in place.

Maybe they have changed the locking behaviour on the newer models?
 

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As I have posted in other threads the truth around CCS problems aren't so black and white, with the blame lying somewhere between RC OEMs and Car manufacturers. I am not sure what you mean about the "i3 Dance" CCS works fine provided the precharge works first time, you do have to faff with the rapid AC connectors, but you shouldn't be using those out of habit anyway...

The tesla plug is part of the CCS standard, known as CCS DC-mid, my understanding that Tesla lobbied for its inclusion, also they don't really implement CCS but I can see it going that way in the future should CCS be extended to better suite there use case. CCS being TCP/IP based is open to more expansion in terms of what can be added, without having to re-engineer the CAN bus.
 

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I think it was @Jack who coined the phrase, some time ago. Something to do with needing to get out, connect and hold the lead while you lock the doors in order to lock the plug in place.

Maybe they have changed the locking behaviour on the newer models?
Did I... :sick:o_O
 

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And to confirm, I've not used a "rapid" AC yet (in a non rapid way), especially as I have the rex. If I ended up somewhere and there happened to be a free one on offer I might, if I wanted to read email in the car, eat a sandwich etc, but I'd not even consider leaving the car beyond a quick pee dash!
 

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And to confirm, I've not used a "rapid" AC yet (in a non rapid way), especially as I have the rex. If I ended up somewhere and there happened to be a free one on offer I might, if I wanted to read email in the car, eat a sandwich etc, but I'd not even consider leaving the car beyond a quick pee dash!
I have only ever done it to clear a check control fault.
 

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As I have posted in other threads the truth around CCS problems aren't so black and white, with the blame lying somewhere between RC OEMs and Car manufacturers. I am not sure what you mean about the "i3 Dance" CCS works fine provided the precharge works first time, you do have to faff with the rapid AC connectors, but you shouldn't be using those out of habit anyway...

The tesla plug is part of the CCS standard, known as CCS DC-mid, my understanding that Tesla lobbied for its inclusion, also they don't really implement CCS but I can see it going that way in the future should CCS be extended to better suite there use case. CCS being TCP/IP based is open to more expansion in terms of what can be added, without having to re-engineer the CAN bus.
I'm told that Tesla were part of the CCS group but walked away when it was clear they weren't going to get what they wanted. My understanding (though sadly I have never found any concrete technical specs or measurements etc to confirm or deny this) is that the Tesla conector is not DC-Mid. DC-Mid is an unmodified Type 2 connector with the 4 phase+neutral pins used instead as a pair of + and a pair of - connectors, with current limit of 70A on each pin (i.e. not much different to the 63A limit for AC charging). Tesla have said repeatedly that their connectors are not made by Mennekes, that they are "more robust" and that a normal Mennekes connector could not cope with the power of supercharging. There's a video somewhere of Elon saying standard connectors would melt if they put 120kW through them. Supercharging runs up to about 340A, i.e. 170A per pin though admittedly only for about 15 minutes continuously. Rumours abound that the pins are deeper or fatter or bathed in unicorn tears or something. The signaling on the Tesla connector is CAN.
 

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CCS being TCP/IP based is open to more expansion in terms of what can be added, without having to re-engineer the CAN bus.
Sure about that?

Don't quote me on it but I'm sure CCS uses PLC to communicate between the rapid and the car.

There was talk about adding PHY for Vehicle to Grid IIRC. This is the same protocol being pushed for smart meters.
 

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PLC for transport, TCP/IP for comms - uses IPv6 too according to overview docs I have, I also think the current PLC implementation is a subset of the full greenPHY standard.

http://electricdrive.org/index.php?ht=a/GetDocumentAction/id/32215
Interesting. My understanding was that they settled for bog standard PLC as the PHY standard hadn't been finalised/ratified when ccs was introduced - could be wrong as haven't looked into this recently.
 

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I would rather have a heavy and awkward plug that is very safe and reliable and copes with hard use outdoors than an easy to use one that cannot take real life usage for long and is consequently unreliable and potentially unsafe. You hear stories of folk having to wriggle charger plug bodies in order to get a good contact, that is a such sign it is on the way out. In plug and sockets for repeated connection and disconnection at EV charger level currents and voltages along with reliable signal transfer and good earthing good quality does not come cheap and they are much more complex to design right than folk might imagine. The marriage of mechanical and electrical connections and interlocks takes a lot of skills to get right.

This stuff can easily kill or maim if it malfunctions or is misused.

The rhyme to remember safety is: 'It is volts that jolts but mills that kills'

A milliamp (mA) is 0.001 of an ampere of electrical current. A small current of a few mA across the heart i.e. up one arm and down the other to get a circuit can kill, so just think what a DC current of 70 amps or more could do in the way of damage.

I once saw the results of an industrial accident where not following working procedures correctly resulted in a battery explosion and severe facial burns and blindness for a young worker. His life was changed in an instant. Do keep safety in mind when using any EV charger. I always inspect for possible damage before use.
 

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Interesting. My understanding was that they settled for bog standard PLC as the PHY standard hadn't been finalised/ratified when ccs was introduced - could be wrong as haven't looked into this recently.
As I have not paid to see real standards, I could neither confirm nor deny that... If they did drop TCP/IP stuff seems a complete waste.

-- Edit
I do actually have a doc that covers using PWM to control, I always assumed it was earlier that that doc, but it might not be. So you could be right they just dropped TCP/IP for first ratified version.
 

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As I have not paid to see real standards, I could neither confirm nor deny that... If they did drop TCP/IP stuff seems a complete waste.
Agreed although IP capability is only really of use if grid connected. last I saw of any 'standard' was before it was all finalised. No reason to look at it recently and wont be paying IEC fee unless I have a reason too :)
 
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