Electronics > Projects, Designs, and Technical Stuff
Troubles powering PWM cooling fan from solar panel
valley001:
Hello all,
I have a battery box that I am ventilating with a 12v PWM fan (salvaged form an old PC). I am powering this fan directly with a 10 watt 12v panel, using the fan ground and positive wires and leaving the green and blue wires disconnected. It worked great at first, spinning the fan up to full speed under good sun. The trouble started with clouds obstructed the panel and the fan diminished speed to idle, when the clouds cleared the fan remained at idle. If I disconnect the fan and reconnect, or momentarily obstruct (completely) the solar panel, the fan will resume full speed operation.
I presume there is a controller in the fan that is unhappy and causing this. Any way to prevent it from locking up in idle mode? I know I could simply use a non PWM fan but this seems like a decent fan and would rather not spend the money if I can make this setup work.
Thanks in advance all.
Prehistoricman:
Dumb idea:
Have a microcontroller control the power to the fan. Cut out the power periodically :)
NiHaoMike:
What you need is a control circuit to adjust the fan speed to prevent the voltage dropping too low.
valley001:
I presume something like this could work? Originally I thought the fan speed would track the solar output but I guess I would need a non pwm motor for that.
https://www.amazon.com/gp/product/B077SLWWXL/ref=ox_sc_saved_title_1?smid=A243HB0NZWY05K&psc=1
NiHaoMike:
Probably the easiest would be to use an Arduino to sense the voltage using a voltage divider and then control the fan using PWM. Or do that with some analog circuits if you prefer to go that route.
Navigation
[0] Message Index
[#] Next page
Go to full version