Why does my kit provide extruder fan wiring extension as a 2 pin, if the fan has 3 pins May 07, 2015 03:47PM |
Registered: 9 years ago Posts: 77 |
Re: Why does my kit provide extruder fan wiring extension as a 2 pin, if the fan has 3 pins May 07, 2015 04:01PM |
Registered: 10 years ago Posts: 569 |
Re: Why does my kit provide extruder fan wiring extension as a 2 pin, if the fan has 3 pins May 07, 2015 04:09PM |
Registered: 9 years ago Posts: 77 |
Re: Why does my kit provide extruder fan wiring extension as a 2 pin, if the fan has 3 pins May 07, 2015 04:57PM |
Registered: 9 years ago Posts: 606 |
Re: Why does my kit provide extruder fan wiring extension as a 2 pin, if the fan has 3 pins May 08, 2015 08:31AM |
Registered: 10 years ago Posts: 869 |
As tadawson said, the 3rd wire is for a tach to monitor the fan's speed. It's only feedback so a computer for instance can monitor the fan speed and take appropriate action should a fan stop working or to provide some basic speed control feedback. 4-wire fans are available that have an additional wire that is a PWM signal for controlling fan speed when more control is desired than just varying the supply voltage. It also allows the fans to run at full voltage which can be damaging to some fans.Quote
Kurzaa
In the case of a computer fan, I believe the third pin is for PWM control of the fan, so you can send a signal to only operate at 80% power or something similar. Otherwise I believe in a two wire setup the power is controlled by manipulating the power sent to the fan.
EDIT: I would assume just using the red and black wires would control the fan just fine. The absence of a signal on the white (?) wire would keep the fan fully on. But I am guessing.
Re: Why does my kit provide extruder fan wiring extension as a 2 pin, if the fan has 3 pins May 08, 2015 10:32PM |
Registered: 9 years ago Posts: 125 |
Quote
tadawson
The third wire is a tachometer signal coming back from the fan, used by motherboards to sense speed, so they can hit a given airflow. Motor is only on red/black, and all speed control is done on those same leads.
- Tim