Our "Voltswagen" has this red "trafo-charger" meant for charging forklifts etc.:
The picture is from before the car was completed.
During charging it gets rather hot, so we've installed a 12V computer-fan on the top of it (not in the picture. the fan was added later) which spins rather fast.
However, me and my friend are having quite a heated argument (no pun intended). He insists that I've installed the fan the wrong way. I've installed it so that it sucks air from outside and pushes it into the box. The charger has air-vents on both sides, about 3/4 of the way up, so in the current configuration, this is where the air comes out.
However, my friend insists that the cooling-effect would be much better if the fan sucked the air out, drawing in air from the side vents. Basically reversing the air-circulation.
So, who's right? I believe that either way works just as good, while my friend insists that the current way traps hot air inside the charger, since the vents aren't at the very bottom.
-Daniel
ps. Here's a vid of the build of the car and the car in action
We're using 48V from 8 12V gel-batteries connected in series-parallell with a total of 220Ah. We're using a Clark forklift-motor at 5.2 kW
http://www.youtube.com/watch?v=QDnR_if1Rao

The picture is from before the car was completed.
During charging it gets rather hot, so we've installed a 12V computer-fan on the top of it (not in the picture. the fan was added later) which spins rather fast.
However, me and my friend are having quite a heated argument (no pun intended). He insists that I've installed the fan the wrong way. I've installed it so that it sucks air from outside and pushes it into the box. The charger has air-vents on both sides, about 3/4 of the way up, so in the current configuration, this is where the air comes out.
However, my friend insists that the cooling-effect would be much better if the fan sucked the air out, drawing in air from the side vents. Basically reversing the air-circulation.
So, who's right? I believe that either way works just as good, while my friend insists that the current way traps hot air inside the charger, since the vents aren't at the very bottom.
-Daniel
ps. Here's a vid of the build of the car and the car in action
We're using 48V from 8 12V gel-batteries connected in series-parallell with a total of 220Ah. We're using a Clark forklift-motor at 5.2 kW