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Case Fan Modification & Replacement

I’m trying to replace 2 very noisy fans in my Proline UPS I2000 and I had to do some research to figure out what was going on. I’ll add as I find more useful information.

My issues started when I could not find a data sheet for my AVC F9025R12UR, which I gather from the new model numbering is a 90mm x 25mm, R= Hydraulic Bearing, 12 = 12V & UR

2, 3 & 4-wire Fans

2 wire

  • Pin 1: Black = Ground(-) or Blue
  • Pin 2: Red = Positive(+12V)

3 wire


  • Pin 1: Black = Ground(-) or Blue
  • Pin 2: Red = Positive(+12V) or Yellow
  • Pin 3: Yellow = Tach Output, sometimes Blue or Green

Looks like the tach reading is basically a voltage i.e. 2.0V = 2000 RPM and 1.5 = 1500 RPM

Industrial Rotor Lock Warning

  • Pin 1: Red = Positive(+12V)
  • Pin 2: White = Rotor Lock Warning
  • Pin 3: Black = Ground(-)

The rotor lock pin has a small voltage +-0.1V when running and goes high when the motor is stopped.

4 wire

  • Pin 1: Black = Ground(-)
  • Pin 2: Red = Positive(+12V) or Yellow
  • Pin 3: Yellow = Tach Output, sometimes Green
  • Pin 4: Blue = PWM Control

Useful Fan Info

Delta Fans

F00 suffix is Tach (frequency) output (open collector), –R00 suffix is Rotor Lock warning (open collector, goes high when locked).


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