I'm working on a circuit for a future project and I'm not familiar enough with the way a power MOSFET would respond in this situation.
Here's the circuit: http://www.innoengr.com/examples/fan_speed_controller2.jpg
What this is for is to change from the existing mechanical fan to an electric one on my motorcycle. The fan I found to fit draws 1.2A in free air on the bench when supplied with 12V.
Obviously it's meant to start turning the fan on at a temperature set by VR2. It takes a good 6V to get the fan started but once turning will operate with less.
I'm wanting it to start when the thermistor senses 180* F and be at full speed when and if it sees 210* F.
Anyone care to suggest some components & values or if I need to alter the circuit to achieve this? As soon as I finish reading through the rest of the new forum posts I've got to move on to completing a project for work they're expecting to be 100% functional come Monday. It's a monster and complex enough that I had a PC board professionally etched. I've got about half the components soldered in but need to finish and test it, hopefully with no need to make any value changes.
Here's the circuit: http://www.innoengr.com/examples/fan_speed_controller2.jpg
What this is for is to change from the existing mechanical fan to an electric one on my motorcycle. The fan I found to fit draws 1.2A in free air on the bench when supplied with 12V.
Obviously it's meant to start turning the fan on at a temperature set by VR2. It takes a good 6V to get the fan started but once turning will operate with less.
I'm wanting it to start when the thermistor senses 180* F and be at full speed when and if it sees 210* F.
Anyone care to suggest some components & values or if I need to alter the circuit to achieve this? As soon as I finish reading through the rest of the new forum posts I've got to move on to completing a project for work they're expecting to be 100% functional come Monday. It's a monster and complex enough that I had a PC board professionally etched. I've got about half the components soldered in but need to finish and test it, hopefully with no need to make any value changes.