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Charging fan

Me again…am I right in assuming that the charger fan stays on even after the battery has charged?

Yes. It should turn off eventually, and pretty well always does if you unplug.

Only the first generation charger stays on after the display shuts off. It deactivates after a few hours. Newer chargers shut off together with the display.

If it’s hot and you start driving after you charged, the fan will sometimes activate for some time while driving (any generation charger).

In over 6000 Miles my Twizy Fan has only ever switched off once after charging while connected to the Mains :slight_smile:


The fan pulls around 30 W btw. You can use a time switch to cut the power.

Not sure it’s as simple as that with the first generation charge. I don’t think there are two different chargers more there are 2 or more sets of firmware. Also I find the ‘overrun’ time is dependent on how long it was left on overrun the last few chargers. So a few times of leaving it charging over 100% until it does shut down appears to shorten the ‘overrun’ time. I did suggest that this overrun period was used to balance the cells in the battery. However that doesn’t sound right on this type of battery - correct for Lead Acid banks. But it would explain why the overrun/ balancing period changes.

However this doesn’t explain why there are different firmware versions. In Oct 12 there was supposed to have been a new firmware version issued. However it was not deployed to the older Twizy’s unless they had the accelerator issue. The I believe newer firmware cuts the power when the brake is pressed.

Lithium batteries do appear to need a period of a much lower “balancing” charge if you want them to be completely “full”. The last half hour of any Twizy charge puts in a very small amount of the total, and some experienced EV owners used to recommend only filling to about 80 - 85% capacity unless you actually need the full range, because it’s so much quicker. I have no idea whether the batteries benefit from a “full” charge, or are degraded by never getting one. I imagine the fans must operate on a temperature sensor, and certainly the more sophisticated chargers use temperature as well as voltage as a measure. I suspect you;re right that there has been a firmware change in the charger (or perhaps this is all handled by the controller, now) to tweek the parameters

Since my charger was replaced and I had a couple of “software” updates, the fan does not stay on after 100% is achieved! before it would stay on until I unplugged it.

the fan does not stay on after 100% is achieved!

The fan switches off as soon 100 % is reached? Or when the display switches off?

Does it not stay on if the charger is warm? Or don’t you know yet as it is still cold when charging?