A breach of trust *UPDATE*

I agree, the title is heavy handed, my dear Zoe. But I thought we had an agreement when I took upon me the responsibility to look after you and take care of you. Have I failed you in any way?

Last night, I set the timer for you to start charging at 05:00. When I switched you off, there was a confirmation message that charging would not start until 05:00. I connected you to the charger correctly, as the green light on the charger confirmed. I pulled both plugs to confirm they were in place and locked. I checked your screens and you did not tell me that there was anything wrong. So I expected the battery to be full this morning.

But you did nothing. You just stood there looking pretty and pretty useless. There was not a single Wh extra in your battery. What is the matter with you? Is such a simple command to complicated for your silicon brain? Or are there little critters in you brain, that the computer people call ‘bugs’?

All wild speculation, let me investigate further before jumping to conclusions. I will report my findings here.


After reading the manual on ‘charging’ again, I have found out what the issue is. My Zoe wants to be in ‘P’ for charging. She doesn’t want to endanger anyone, and because she has no way of telling the handbrake is on, she relies on the transmission in ‘P’ to make sure she stays in place while connected. Would she roll away while charging, she could rip a plug from either socket and expose live wires to the public. Not good.

But my Zoe is not entirely in the clear on this. Her communication skills are a bit lacking and the consequence of not putting her in ‘P’ could be more explicit. When I switch her off with the transmission not in ‘P’, she shows a warning message on the dashboard, accompanied by a bleep, suggesting me to put the transmission in ‘P’. But it looks more like a friendly reminder than something important. My Zoe was on level ground with the handbrake firmly on, so I ignored it and forgot about it. So many new bleeps to get used to. After plugging in, the dashboard showed the message ‘Ongoing checks..’, which is a normal message that my Zoe displays each time she starts charging, sometimes these checks take more time than I have patience for. So I ignored that message and expected that after all checks were done and handshake protocols with the charger complete, she would surely start charging.

I have found out that she gave another clue. I had to find that out myself, because the Renault people did not write everything in the manual about the ‘secret charging indicator morse codes’. I can not blame my Zoe for this. If she is all set up correctly and ready to charge then, after charger handshake is complete, she double-blinks her external charging indicator and the wall charger will show a blue light, as if she is charging. This lasts for about 2.5 minutes, then all indicators revert to normal ‘connected but not charging’ mode (external charging indicator is off, wall charger shows a green light).

I will tell the Internet people all about your charging protocols later, but for now, my dear Zoe, all is well again between us.


6 Comments on “A breach of trust *UPDATE*”

  1. Adam says:

    Do you normally park in Neutral? Perhaps this is a culture difference but I have never known of anyone not to use Park when parking. What is the downside here? Not to be callous but this one seems obvious..

    • electrophile says:

      No, I changed it from P to N because I thought it looked better on the pictures and ‘forgot’ to put it back in P. Before my Priori I drove a manual and yes, those you usually do put in neutral when parking. A Prius will select P automatically when switching it off so I never had to worry about that. Now I’ll have to learn a new habit.


      • Alex says:

        I think that in all US automatics sold after about 1995, you cannot take the keys out, unless you first put the auto gearshift lever in Park. That’s why it may sound surprising to automatics drivers.
        In pre-1990 US-Cdn automatics it was possible to take the key out in Neutral.
        BTW I know that many European drivers of manuals would leave their car parked in 1-st gear, without engaging hand-brake. It may be even safer than handbrake alone, unless some kids or even a dog (except very small ones) were left in the car.

        Happy motoring!
        I heard a French joke that in Holland “the worst drivers are given yellow licence plates”.
        Looks like the first week you you drove faster (141 kph) than Zoe’s max speed from French Renault site (135 kph). Not everybody can drive fast and safely, or follow closely, only the skilled ones.


      • electrophile says:

        The 141 km/h was from the speedometer. It exaggerates by approx. 5 km/h, so the official 135 km/h seems likely correct. I was on a stretch of motorway with a 130 km/h speed limit and where everyone drives at those speeds or more, so no safety was compromised!


  2. Alex says:

    I think that the real reason Zoe can only be charged in ‘P’ comes from the way charger operates (more on this below), not from safety reasons you mentioned (don’t know how other EVs handle it).
    Actually it would be often desirable to move the car forward or back half a meter (with a warning beep on) while charging for many hours, i.e. without disconnecting the cable, and repeating system test procedure.

    Read this:

    It says for the e-motor:
    can be used either as a motor (for driving the vehicle), as a generator (for charging the battery

    while driving) or as a TRANSFORMER (for external charging at the mains).

    So it looks like they use motor as a transformer when charging, and to do that, it is likely they do some power hardware reconfiguration.
    The Continental motors used by (? all current) Renault EVs are synchronous AC, 3-phase, motors with wound rotor, which is excited with a DC current (most big hydro generator have the same design).
    I guess that, when used as transformer (charging), stator is transformer’s primary, rotor secondary, and rectifier needs to be added (to rotor output), or existing power electronics that controls rotor DC current in motor mode needs to be reconfigured for transformer-mode operation.

    On the site above there is hi-res image of Conti motor with integrated reducer and the P lock, apparently, it may contain differential, or may not.
    A year or two ago I read specs (on French Renault site) for EV Kangoo and Fluence. Motor weight was also given (not now for Zoe). They were very heavy for their power output, (140 and 160 kg), at least compared with motor in Tesla Roadster, and AC Propulsion motors (PM based motors in Leaf and Prius/Ford/Volt are supposed to have high power density, but not high temporary overload capacity).

    On wiki now it says Fluence ZE motor is 160 kg, stronger than in Zoe, same max speed, max rpm 11,000.
    Probably similar max rpm for Zoe.

    As the motor (reducer) engages some hardware lock when ‘P’ is selected, the locked position of rotor vs stator (or primary vs secondary) vary, depending where exactly the car was stopped (see the shape of rotor).
    It is possible that magnetic resistance to the flux in transformer mode varies by a few percents, depending where exactly the car was stopped/parked, and so varies the time needed to recharge the given amount of energy, other conditions the same.
    It could be measurable (small diff in charging current) , by moving car by 1/16 of one motor rpm (rotor has 8 spokes).

    BTW do you know the max rpm of that motor (at Zoe’s max speed), any diagnostics display mode to see it?

    How many power wires connect to the motor, can you see (often motor is too low under inverter) )?
    (At least five, perhaps more, 3 to stator, 2 to rotor).

    Is it liquid or air cooled?

    Perhaps its extra weight allows it to have air cooling and integrated transformer, so it’s not too bad, fewer components to fail.

    Rotor has slip rings – brushes will need to be replaced after certain mileage (surely more than 100,000 km), you may ask Renault, or it will be next owner’s worry.


    • electrophile says:

      Hi Alex,

      Thanks for the very interesting info. I have not yet collected enough technical info on the Zoe to judge this. Your explanation sounds very plausible.

      Your suggest that power can vary during charging, depending on the exact position the rotor was in when engaging ‘P’. I have checked quite often and my Zoe is always charging at 8.8 kW, so there are three possibilities: the position of the rotor does not matter, the electronics compensate for the suboptimal alignment or the ‘P’ forces the rotor into the correct position (if this is at all possible).


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