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Hi there,

Just to add - i've had one of these cars, it is i-mievs from 09/10 that were "pre-evse", i.e. do not communicate on the pilot wire and just expect 240v applied to the charger. Your best bet is the "twizy adapter" mentioned above which will allow reliable charging at any type 2 post.

These cars charge at a fixed 12A, ie ~2.9kw so charging on an extension lead is particularly difficult with these early models. Also advisable to plug the car in BEFORE switching on the power because otherwise the pins on the type 1 adapter that goes into the car are live at mains voltage !!
Ouch! Didn't realise its 12A. Have you measured that yourself ?

In that case a Twizzy adaptor might struggle due to the 3 pin plug not really being designed for a continuous 12A over long periods of time that it takes to charge. So a custom cable that cuts out the additional 3 pin plug might be best... Hmm..
 

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Ouch! Didn't realise its 12A. Have you measured that yourself ?

In that case a Twizzy adaptor might struggle due to the 3 pin plug not really being designed for a continuous 12A over long periods of time that it takes to charge. So a custom cable that cuts out the additional 3 pin plug might be best... Hmm..
Yeah actually this is a great point... would be possible to use the same wiring as the adapter plug I have, but wire it to a j1772 type 1 plug on the other end. You'd end up with the best of both worlds: ability to tell the charger to give you current + ability to stop the charge, and also not melting anything. :)

If you look at the spec, you could probably just modify an existing type 2 to type 1 cable by cutting the CP wire and then adding some resisters + a diode + a switch (like my mod) in the plug on the charging post (type 2) end. I don't think you need pwm under 16 amps, but maybe someone else can advise better.
 

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Ouch! Didn't realise its 12A. Have you measured that yourself ?
Yes indeed, I had a 2012 car where the OBC had failed and someone had fitted one from an 09 imiev, i.e. a pre-evse "dumb" charger and it didnt communicate on the pilot wire but just had 2 fixed charge rates, based on whether it was supplied 120v or 240v ac, the 120v one was 8A I think and the 240v one is 12A. I measured it myself yes with a plug in power meter ! I was worried it wasnt working correctly but found another guy with a similar car and chatted to him and he measured the charge rate and confirmed its 12A, he said it works OK, just the plug gets a bit warm in summer...

If you think about it, the i-miev gets away with 12A charging because the battery can take on about 12kwh when new, maybe 10kwh after several years, charging at 12A is ~2.9kw, thats about 2.3kw going into the actual battery, so about 4.5 hours charging. Then you have the pausing for balancing mid charge and the fact that it isnt often charging from 0%, so maybe 4 hours is the most it charges for, more often 2-3 hours and as its not so many hours it works OK on the 12A. Yeah its not ideal but it does work.


Yeah actually this is a great point... would be possible to use the same wiring as the adapter plug I have, but wire it to a j1772 type 1 plug on the other end. You'd end up with the best of both worlds: ability to tell the charger to give you current + ability to stop the charge, and also not melting anything. :)

If you look at the spec, you could probably just modify an existing type 2 to type 1 cable by cutting the CP wire and then adding some resisters + a diode + a switch (like my mod) in the plug on the charging post (type 2) end. I don't think you need pwm under 16 amps, but maybe someone else can advise better.
If the trailing socket on a twizy adapter is just literally a socket then you could swap this for a 16A commando socket and put the same on your charge cable but what I dont know about a twizy adapter is whether it is setup to communicate with the charging post at a certain charge rate which matches what the twizy wants - if this is less than 12A then you'd probably confuse the charge post if the adapter asks (via the pwm comms on the pilot wire) for say 8A for a twizy, then the i-miev pulls 12A this might cause the charging post to stop charging with an error.

Im honestly not sure what the answer is for making an early i-miev charge properly on type 2 posts, I always presumed the twizy adater would work but never actually tried it. The guy at evbitz can probably come up with a solution, he is a clever guy and can make cables to order. The twizy adapter might work on some posts but really you need an adapter that correctly asks for 12A. I tried working out how to make my dumb charger communicate on the pilot wire but the internals of the OBC were very different, lots of changes and somewhere in there is the stuff to communicate with an EVSE.

Cheers
 

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Yes indeed, I had a 2012 car where the OBC had failed and someone had fitted one from an 09 imiev, i.e. a pre-evse "dumb" charger and it didnt communicate on the pilot wire but just had 2 fixed charge rates, based on whether it was supplied 120v or 240v ac, the 120v one was 8A I think and the 240v one is 12A. I measured it myself yes with a plug in power meter ! I was worried it wasnt working correctly but found another guy with a similar car and chatted to him and he measured the charge rate and confirmed its 12A, he said it works OK, just the plug gets a bit warm in summer...
Good to know. The later ones charge at 9 amps on a 3 pin granny charger and 13 amps on a full Type 2 EVSE.
If the trailing socket on a twizy adapter is just literally a socket then you could swap this for a 16A commando socket and put the same on your charge cable but what I dont know about a twizy adapter is whether it is setup to communicate with the charging post at a certain charge rate which matches what the twizy wants - if this is less than 12A then you'd probably confuse the charge post if the adapter asks (via the pwm comms on the pilot wire) for say 8A for a twizy, then the i-miev pulls 12A this might cause the charging post to stop charging with an error.
The situation is worse than that. An EV (in this case the special adaptor pretending to be a car) using AC charging can't "ask" for a certain charge rate, that's not how the signalling works. The EVSE advertises to the car how much current it is allowed to draw using PWM on the pilot signal and it is up to the cars on-board charger to remain within this limit. The car can't communicate back to the EVSE what current it wants, as it wouldn't do it any good to do so anyway as the EVSE would not be able to supply more power just because the car asked for it.

So the twizzy adaptor can be aware of the limit advertised by the EVSE but can't do anything with that information as the car is effectively just a 3 pin load which can't be told what to limit it's current draw to. All the adaptor could do really is to monitor the current drawn by the car and ensure that if the car drew more than the EVSE allowed, shut down the charge to prevent overloading the EVSE, but it couldn't throttle the car. If it doesn't, the EVSE itself may shut down instead, as some public EVSE's are known to abort a charge session if a car draws more power than allowed for more than a short (surge) period of time.

In practice most public EVSE's probably support at least 16 amps so it wouldn't normally be an issue but it might cause a problem if there was load balancing or the EVSE used dynamic throttling like a Zappi in solar power mode which can drop below 3kW - it would signal the car to reduce current but the car would ignore it.
Im honestly not sure what the answer is for making an early i-miev charge properly on type 2 posts, I always presumed the twizy adater would work but never actually tried it. The guy at evbitz can probably come up with a solution, he is a clever guy and can make cables to order. The twizy adapter might work on some posts but really you need an adapter that correctly asks for 12A. I tried working out how to make my dumb charger communicate on the pilot wire but the internals of the OBC were very different, lots of changes and somewhere in there is the stuff to communicate with an EVSE.

Cheers
The upgrade harness I linked to earlier that converts the car to J1772 would be the most correct and ideal solution, however it apparently only works for a "changeover" MY10 car, so not sure how you could tell if the car was suitable for the new harness, and the cost of getting it and fitting it would be significant.
 

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Thanks for all your help everyone. I managed to get to the charging station this morning when it was free and after one try where I thought I was definitely screwed, it worked on the second one. It is now there charging though not entirely sure how long it will take. Gonna go back and check on it tonight around 7-8pm and see what that has gotten me.
So how did the charging go ?
 

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So the twizzy adaptor can be aware of the limit advertised by the EVSE but can't do anything with that information as the car is effectively just a 3 pin load which can't be told what to limit it's current draw to. All the adaptor could do really is to monitor the current drawn by the car and ensure that if the car drew more than the EVSE allowed, shut down the charge to prevent overloading the EVSE, but it couldn't throttle the car. If it doesn't, the EVSE itself may shut down instead, as some public EVSE's are known to abort a charge session if a car draws more power than allowed for more than a short (surge) period of time.
mmmmmm interesting, so I guess a twizy adapter with the trailing socket cut off and fitted with a 16A commando socket, then a cable with a commando on one end and type 1 on the other should work with a pre-evse i-miev, BUT is not that safe because it can more easily operate outside the charge point's power requirements (wouldnt work on a 3kw post for example, or one which is subject to any kind of load sharing, as the car wont get or respond to that message). Plus anyone could disconnect your commando socket as they choose since its not locked. Its not a great solution, tho probably would work.

The upgrade harness I linked to earlier that converts the car to J1772 would be the most correct solution, however it apparently only works for a "changeover" MY10 car, so not sure how you could tell if the car was suitable for the new harness, and the cost of getting it and fitting it would be significant.
Yes this is just for a very small number of cars, this is where the car has the new OBC which can communicate on the pilot wire but the wiring from the type 1 socket doesnt have the pilot wire. My car definitely had the wiring from the type 1 socket because it used to charge with a standard granny cable before the old charger went pop, but didnt communicate once the old "dumb" on board charger had been fitted (which I have to say really confused the mechanics.....!).

Cheers.
 

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mmmmmm interesting, so I guess a twizy adapter with the trailing socket cut off and fitted with a 16A commando socket, then a cable with a commando on one end and type 1 on the other should work with a pre-evse i-miev, BUT is not that safe because it can more easily operate outside the charge point's power requirements (wouldnt work on a 3kw post for example, or one which is subject to any kind of load sharing, as the car wont get or respond to that message). Plus anyone could disconnect your commando socket as they choose since its not locked. Its not a great solution, tho probably would work.


Yes this is just for a very small number of cars, this is where the car has the new OBC which can communicate on the pilot wire but the wiring from the type 1 socket doesnt have the pilot wire. My car definitely had the wiring from the type 1 socket because it used to charge with a standard granny cable before the old charger went pop, but didnt communicate once the old "dumb" on board charger had been fitted (which I have to say really confused the mechanics.....!).

Cheers.
I think most of the basic public chargers are generally at least 16 amps or 3.7kw, so I don't think 3kw is the actual limit. Since you are unable to pull more than that, I'd suspect that unless it was to dip below, you're probably within tolerances.
 

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Discussion Starter #48
So how did the charging go ?
Hiya, sorry, I've been away a lot over the last month so not been online much. I ended up getting a convertor from Symphony and it has been great with the ubitricity lampost chargers. Source London chargers are a pain because they have a specific connector for use which doesn't work with my car as discussed earlier in this topic. The car has been great since then, however I have a new problem now which I'm going to start a new topic on shortly after I've done a bit of research. But basically my car won't start. Remote won't lock/unlock the car (changed the battery recently). The starter won't turn at all. Joy!
 

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Hiya, sorry, I've been away a lot over the last month so not been online much. I ended up getting a convertor from Symphony and it has been great with the ubitricity lampost chargers. Source London chargers are a pain because they have a specific connector for use which doesn't work with my car as discussed earlier in this topic. The car has been great since then, however I have a new problem now which I'm going to start a new topic on shortly after I've done a bit of research. But basically my car won't start. Remote won't lock/unlock the car (changed the battery recently). The starter won't turn at all. Joy!
You know Source London chargers have a type 2 socket as well as the type 1 lead?

I'd have thought the cable you use for ubitricity would fit in there.
 

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Discussion Starter #50
I did try it at the time, but I've been meaning to go back and try it again, as I thought it possible that my convertor key switch may have been turned to off. However it isn't my nearest option so I've not been that bothered. It would be handy to know in case of emergencies though.
 

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I did try it at the time, but I've been meaning to go back and try it again, as I thought it possible that my convertor key switch may have been turned to off. However it isn't my nearest option so I've not been that bothered. It would be handy to know in case of emergencies though.
I did that to myself this weekend on Ubitricity... completely forgot the key in the wrong position and kept wondering why it wouldn't power on 😭. Finally realized my mistake and felt silly, haha.
 
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