Subject: Temp Controller problem
By: Rob (IP: 76.170.130.*)
Written on: 10-02-2010 03:53

I built the Temperature Controller to use on an old cpu fan to help cool my xbox.
The fan is running off a 5v usb. The problem I\'m having is that it seems to take a lot of heat to get the fan running. I have to put a hair drier on it or hold it over a flame to get the fan running. I have adjusted the potentiometer and have it turn fully to one side. Any suggestions?

By: Tillmann (IP: 92.230.59.*)
Written on: 13-02-2010 20:58


it seems that either the pot or the NTC has the wrong rating. Both should be 10K.

The circuit is mostly tested with 12V, although it should also work with 5V if the MOSFET is suitable for this voltage.

By: Rob (IP: 76.170.130.*)
Written on: 15-02-2010 19:46

I\'m using all the same parts in the guide.
10K thermistor (271-110)
10K pot (271-343)
and 60volt N-Channel mosfet (276-2072)
The only problem I can think of is if the thermistor is old. Since I couldn\'t find one at radioshack, I searched my science lab and found an old Archer package that has this one. It was still in the package and has the same serial number as the one in the guide.

Since I don\'t really need the fan to ramp up or down with the temp, I really just need it to turn on full blast at a certain temp, can I eliminate something here?
By: Rob (IP: 76.170.130.*)
Written on: 20-02-2010 16:55

I used a 9 volt battery instead of usb and it works now. I guess maybe the 5v wasn\'t enough to get the fan started? I don\'t know. But the 9 volt works. Thanks.
Back to index | Reply to this message

Forum software based on code ©