PV1 wrote: It seems to me that the pause is screwing with the station and the station could be ...
It's hard to know what is happening without special equipment. I think that there has to be a firmware issue with the ChargePoint EVSE, whereby it's not handling the pause correctly, at least under some circumstances.
It will be difficult to get through to them that they have an issue. I think that some software engineer at ChargePoint needs to have an iMiev that frequently pauses to test with and debug their code. I wonder how this could be facilitated.
Edit: maybe it's like this. The site has a total available power of 4.4 kW. There is another vehicle charging initially; when the iMiev starts charging, they each get 2.2 kW each. Good so far.
Other vehicle stops charging, iMiev gets 3 kW, another vehicle starts charging, they both get 2.2 kW again. Still good so far, but each time the power share is changed, some vehicle started or stopped charging
. Now the iMiev charge current goes to zero in the pause. The EVSE isn't expecting this. Maybe it assumes that the iMiev has stopped charging, so it can allocate 3.3 kW to the other vehicle. Still all good.
But the EVSE puts 1.1 kW on the pilot for the iMiev, since that's all that's left over, and the iMiev hasn't completely finished charging; the handshake isn't complete. Now the iMiev starts drawing current again, and the pilot says 1.1 kW so that's what the iMiev charges at. The EVSE should be sharing the current equally again, but because this isn't the start or end of a charge, it doesn't do so. Finally, the other vehicle stops charging, and the EVSE re-allocates the power share, 3.0 kW to the iMiev and 1.4 kW on the pilot for the other vehicle (in case it starts charging again? Seems unlikely.)
So according to this guess of mine, the problem is that the ChargePoint EVSE only shares the power when a vehicle starts or finishes charging, or when the power goes to zero. It should be sharing all the time, or at least say once per minute. For example, as the iMiev charge rate is tapering down, the power available to the other vehicle should be tapering up. This sounds like a pretty simple fix, but it requires getting the idea that they have a problem to the appropriate engineer. Maybe the above graph could do it. But how to get the attention of the right person?
I have a similar problem with Voltronic Power inverter-chargers. They have an easily demonstrated charge bug, and a colleage and I have posted about this and emailed them repeatedly, but it never gets fixed. Meanwhile, our patched firmware that fixes this problem is quite popular. (And no, I don't have the facilities to patch EVSE firmware.
)[ Edit: "started charging" -> "started or stopped charging". ]