Grow Room Simple DC Fan Speed Control

[KapScot]

http://pcbheaven.com/circuitpages/A_Simple_Way_To_Reduce_A_DC_Fan_Speed/

I stumbled across this link looking for replacements for my 3 old Antec 12V PC fans - these had a little switch cable on each fan with three fan speeds - which is, as I'm sure we are all aware crucial in tuning airflow. These days such fans are controlled by the computer settings - which we can't use when using for grows.

To much blow = to hot - too much in that direction = too hot - move it from blowing from one corner to another and wooosh might as well switch off the lights. Cooling in small spaces is a dark art, and even though I now have a double size office cabinet it remains a challenge.

Since many people are modding PC cases I thought it might be useful (old skool) info even tho the author sounds pretentious the theory is sound - that's exactly what the Antec controllers were doing.

I was thinking of re-using the switches on newer fans but it was the switches not the fans that died first on the Antecs \o/ so get decent switches.

 

[thelastrebel]

Nice guide to a cheap and easy way of doing it, I like that. I'm in the process of building up the components to put a PC case together and I went with a Noctua PWM controller which works really well, but the cost would be prohibitive if I wanted more than maybe one in the case really. The case I'm going to use has a built in 3-way switch that I'll probably use for internal airflow fans but I have an idea to put together a thermoelectric temperature control system that will need a couple of fans and I might do something like this to have a cheap and easy way of controlling those. Cheers!

 

[KapScot]

Yer it works well - I've replaced a couple of mine that were getting noisy - and for stealth silence the Noctuas are good (but I found not good close to surfaces, they really want some intake clearance (different models will vary - I don't have a box to hand but mine were the quietest I could get for the airflow) so lack of torque to suck in air was an issue when they are within a few inches of a surface).