120 mm fan bracket for Renault Twizy on-board charger

thingiverse

The Renault Twizy has an on-board charger called Elips 2000. Unfortunately, Renault has not designed sufficient cooling around the charger. Even when charging on moderately warm days, the Elips' specified temperature range can be easily exceeded. This is possibly the reason why Twizy chargers often die. It also leads to the Twizy reducing the charge power, resulting in longer charging times. Some Twizy owners add extra cooling using auxiliary charge fans. This model is a bracket/mount for installing 2x 120 mm computer fans above the charger. "Slim" (15 mm thick) fans should be used. There is about 30 mm headroom available above the charger, and standard thickness computer fans (25 mm) would probably impede the air flow. ## Printing Print 2x of `Fan_spacer_single`, 1x of each of the other parts. `Fan_bracket_2x12cm` is pretty long, you might have difficulty fitting it in the printable volume of your printer. I could _just_ fit it by rotating it 45 degrees, so it's diagonal on the build plate. (Ender-3 V2) ## Other parts needed * 2x 120 mm wide, 15 mm thick computer fans. I used Corsair AF120 Slim. * A set of suitable screws. I used the screws that came with the fans. * One cable tie. * Some way of connecting the fans to power and switching them on/off (see below) ## Assembly See photos above. I used the shorter screws to fasten the fans to `Fan_bracket_2x12cm`, and the longer screws to attach `Fan_spacer_single` and `Fan_spacer_double`. Note the direction of airflow. The fans should blow air downwards, and the 3D-printed parts should be installed on the underside. ## Installation Remove the Twizy floor panel by the pedals. The assembled fans/brackets should slide right in and then a bit sideways so you get ~1 cm clearing between the left fan and the parking brake cables. A notch in the frame of the Twizy should line up with the prongs of the 3D-printed part. The hole in the 3D printed part should line up with a hole in the Twizy frame, use a cable tie through these holes to affix it at this point. ## Powering the fans You only need to connect pins 1 (GND) and 2 (12V) of each fan connector to power the fan. Pin 3 is an optional speed sensor (tachometer) output, and pin 4 is an optional PWM speed control input. If pin 4 is disconnected, the fan runs at full speed. [3 pin and 4 pin fan wire diagrams](https://landing.coolermaster.com/faq/3-pin-and-4-pin-fan-wire-diagrams/) ## Controlling the fans It's up to you how to control the fans on or off. E.g.: * A manual switch * Build your own control circuit with a temperature probe * If you own an OVMS 3, [it can control the fan for you](https://docs.openvehicles.com/en/latest/components/vehicle_renaulttwizy/docs/aux-charge-fan.html) ## Caveats Keep in mind that water can splash up from the road when driving. The charger and the other standard electrical parts at the bottom of the car are protected from water ingress, but computer fans are not. If you drive through a deep puddle, it might ruin the fans and they will need to be replaced. Consider waterproofing your control circuit, or placing it higher up in the car. Consider putting a low-value fuse (e.g. 1 A) on your power feed, in case you get a short circuit.