Maker of Awesome | User 1615
- Mar 6, 2017
PWM 3-Pin Adapter:I wasn't sure it was possible until I did it. I have an adequate understanding of electronics in theory, but I don't often get to make myself real circuits. I knew though, that transistors act as switches when used properly. I used that and developed the idea in my head, and then I made use of my rudimentary google-fu and came across this post.
"Perfect," I thought, "I wasn't the only one to have the idea!"
And so I pushed forward after a couple days debating between building what the original poster's question suggested and the more robust solution provided in an answer given. I used what components I had on hand, an intermediate resistor and a 2222A transistor, and assembled as above - also as a schematic here (image found on the post):
After a couple false starts, mostly due to me inserting both ends upside down, I actually got it to work! The Alphacool DC-LT pump inside my Kelvin T12 is no longer hideously noisy! Unfortunately, the circuit itself is hideous. I'll have to use solder and the appropriate connectors next time, and then get it sleeved.
I don't have much in the way of RPM data at different PWM levels (probably need to re-crimp that wire), but I did manage to go from ~2311 RPM at 100% PWM, to ~760 RPM at 80%, according to the ASRock Tuning software. I was using a low noise adapter also.