Cooling fan hookup?

[sluggie24]

I would like to install a cooling fan on my 9920 controller when I build my truck just to make sure it wont overheat. I have a micro fan made to go on a 540 motor heatsink that seems to have a very low current draw.(although I haven't measured it yet) My question is what would be the best way to hook it up? I was thinking I could tie it into the output line of the Kool Flight BEC I will be running.Would this work without causing any problems for the reciever? If this will cause problems is there a better way to tie it in to a voltage source?

[joostin420]

hmm, i usually attach my cooling fan leads before the controller - so i would probably put them before the Ubec or even at the same location.

justin

[sluggie24]

I thought about that but I dont think the fan motor can handle the voltage from 20 cells. Its probably made for 7.2v. Maybe it can handle 14v at most. I know it would work on the 6v from the kool flight without cooking but I'm not sure about it causing interference or drawing too much power away from the servos, or even burning out the kool flight. I guess I should take my voltmeter home from work and check the amp draw it has? Was really just wondering if anyone else has done something like this and does it work without problems?

[Nick]

Put it in a spare RX socket. Thats what I did, runs off 6v.

[Scott711]

I was wondering the same thing, so I did an experiment with a cpu fan I had laying around. It is rated at 12 VDC and 0.18 amps on the lable. I just cut the leads and touched them straight to the battery leads of my 5s lipo set (18.5 volts). It ran fine so I straped it to the motor for a test run and It seems just fine, kept the motor cooler and didn't blow up or anything from excess voltage.

To hook the fan into the system I just terminated the pos. & neg. leads from the fan to the same connectors I use for the esc, ubec and lvc so all leads are soldered to the appropriate terminal and then plug the whole thing into the batteries. I guess time will tell if it burns up the fan prematurly.

[squeeforever]

if you mean you want to run one on the motor and one on the esc then i would just get a Y addapter and use the 3rd channel in the reciever or in the one for a reciever pack.

[RC-Monster Mike]

I use a 5v fan, plugged into the 3rd channel on the receiver. Works great. Easy to hook up and replace. Perfect. :)

[Scott711]

Can you get these fans with the plug already attached and if so where. If not where can you get the plug to attached to the fan leads. Thanks

[RC-Monster Mike]

I install the plugs myself, actually. I have these little kits that you build onto the wires from the fans(build into a receiver plug). Takes a few minutes, but then it is plug and play.

[sluggie24]

I would hook up to the 3rd channel but I'm using it for the shift servo still. I think I'm just going to tie into the BEC output wires and see how it works. I don't think this little fan should drop the voltage to the reciever too much.......I'll let everyone know how it works when its finished.

[Sneeck]

You can also place a small resistor from 1 pack to the fan to limit the volt's.

[sluggie24]

I was thinking about that too but I think a resistor would "waste" too much electricity compared to the fan alone. Even though I'm going for power in my truck I want to keep as much run time as I can.

I run a couple of 12v pc fans straight from the main cells.
at 22v they do spin some :030: never last too long though :027:

[BrianG]

Originally Posted by cabking

I run a couple of 12v pc fans straight from the main cells.
at 22v they do spin some :030: never last too long though :027:

Put those two fans in series instead. Assuming they are rated the same current/voltage, each will get 11v and will last longer.

Using a resistor is not really bad as long as it is used to control one fan and that fan draws .2A (200mA) or less. To find the resistor value, just subtract the fan voltage from the supply voltage, and then divide that by the fan current. To find the power rating for the resistor, simply square the current, multiply by the resistor value, then double the final value for safety. Usually a two or 5 watt resistor is fine.

If CH3 is being used, hooking them to the output of the BEC. or the output of the on/off switch would be the best choice IMO.

Originally Posted by BrianG

Put those two fans in series instead. Assuming they are rated the same current/voltage, each will get 11v and will last longer.

Now were's the fun in that?
thay last about 2 months..thats good enough for me :003: