Fitting an extractor or CPU cooling fan to a housed controller.

[Magzy]

Now it's turning into winter here in Australia there's limited need for this mod but I'd like to have a solution in place for next summer whereby I can connect a CPU cooling fan with a heat sink to my external controller.

Temperatures get up to 45 degrees celcius here - and that's in the shade - I reckon the controller will just die under these conditions so I'm super cautious here.

So my quest is to attach a FAN & heatsink onto the controller as a means of getting more air flow around it to cool it down - currently it's not getting much air flow.

My controller is currently in an open electronics box which is inside my waterproof panier bag along with the battery but I want to put the lid on and tuck all the lose wires in there and have a distinct airflow constantly going through it.

As with the LED lights which can be powered from the controller. I'm assuming that I can just attach the Pos and Neg wires of a salvages computer fan or CPU fan to the controller box. Switching the fan on and off when neededwith the push of a button - maybe the lights switch below the cruise button would work?

Any thoughts here?

[MonkeyMagic]

Wire 3 or 4 fans together in series depending if you have 36 or 48v

Heat is mainly generated on the underside of the controller, so maybe you will want to mount the fans underneath to constantly cool the aluminum plating.

Buy a cheap auto engine thermometer (just bought 1 for $8 on ebay....) place the sensor on top of the FETS inside the controller. (when you take it apart, the FETS sit pushed against the wall of the enclosure, so stick it ON TOP of these, in other words not on the heatsink paste side, the side closest to the PCB)

My thermometer has an alarm output so technically I could use that to cut off the controller at 60deg cel PCB heat.

Also, where are you in Oz to be getting 45deg!! I'm in Melbourne so forgive my ignorance on heated weather

Good thinking being safe rather than sorry mate!

[DirtyGinge]

how about a drive bay for housing PC hard drives...you can get them in aluminium with fans at the end....good for more heat dissapation...

http://www.amazon.co.uk/3-5-IDE-Aluminum-Enclosure-COOLING/dp/B000PKIXMW
there are larger versions for whatever size you need

[MonkeyMagic]

how about a drive bay for housing PC hard drives...you can get them in aluminium with fans at the end....good for more heat dissapation...

http://www.amazon.co.uk/3-5-IDE-Aluminum-Enclosure-COOLING/dp/B000PKIXMW
there are larger versions for whatever size you need

True, good point but you would need to run a seprerate power supply in that case, and those 3.5" external cases are nearly twice as big as the GM external controller... Then again that could be a good thing dispersing the heat, so if it fits I would definitely look into that

Because of the mounts etc. I saw the best method would be using a peltier plate(s) + heatsink sandwiched on the external controller set to 15deg cutoff or something, but you would need a temp controller or switch via a compiled microcontroller. Not sure if a fan or 3/4 can cope with ambient temps and when the controller generates the most heat is in peak currents so it would just die anyway using fans if it exceeds around 75degrees celcius

Remember, although China is colder in Winter than Australia, it is just as hot if not hotter with the humidity compared to anywhere in Oz. If there was a heat and potential electronics damage contest, I would put all my money on China....

Having said the above, I will say that on a 30+ degree day I was full throttle for quite some time before using regen pulling upto a set of lights on my first build. When the lights went green I tried to take off and all I had was 5 beeps... This was on an internal controller and was the older PCB. I have dual drive with the newer (MX-319) PCB and it has since never had an issue. I say now that GM have identified the problems and have set (or limited as such) the controllers to take quite a beating.

As long as you are not 'revving' the throttle, or vigorously using regen I would say you will have NO issues at all, and the air cooling from the speed of your bike will do far more than mounting any fans in ambient environment. Try to mount the controller somewhere where the bottom gets air flowing past it (example- not enclosed) and it will be fine, in fact chuck a four n twenty pie in there with sauce and perhaps a pasty as well and it will still get you from A to B and probably to C too if she is up for it

Magzy, come to Melbourne I totally want to race you lol - pink slips ?

[DirtyGinge]

To be honest if you want real cooling, I'd go watercooling.

I have been involved in making watercooled overclocked PCs for a long while... you can build a pretty robust cooling solution....have your controller in as secluded a spot as you like, and have a radiator in a wide open position....you can even get non-electrically conductive liquid based on antifreeze ( in any colour ...crazy straw effect anyone  ?)..( I would not use water in a pc)....it would be immensely effective...... expensive but ultimate..do it the right way and you would be lucky if your fets get above 20C under peak load.....

All the components could run at 12V DC, needing only 1 DC-DC converter ( which coincidentally my main man Edward Lyen can supply a variable dc-dc converter at $15 dollars... using 1 to run my Hope dual LEDs off my main battery pack.

Overkill of course, but if you really are dealing with total desert etc..

If you really really wanted to go overboard you could use the same cooling circuit to cool the windings...

[Magzy]

How would I wire up a cpu fan running at ~3v to the controller?

Is there a basic wiring diagram knocking about?

p.s. Monkey - am in sydney - these temps are in the shade... http://wiki.answers.com/Q/What_is_the_highest_temperature_ever_recorded_in_Sydney

[MonkeyMagic]

How would I wire up a cpu fan running at ~3v to the controller?

What CPU fans are 3v?? Must be newer ones. All the surplus ones I have are 12v in that case you can wire 4 in
series. DC-DC converters are cheap anyway.

Also, you posted the hottest day ever in Sydney For that year, maximum average was 31.2deg celcuis as opposed to Melbourne that was 26.9deg

Having said that, hottest day for melbourne was 47.6deg! I was seriously sunburnt that day lol