Locked Rotor Alarm Signal Output (yellow wire lead): Under normal conditions a locked rotor alarm signal outputs a constant signal frequency... if the fan stops spinning or "locks", it then outputs a "LOW" condition signal. If the fan starts spinning again, the "LOW" condition signal will go away.
 
Features:
 
Dimensions: 50 x 50 x 10mm (1.97 x 1.97 x 0.39")
Mounting Center: 40mm (1.57")
Rating: 12VDC
Current: 0.1 Amps
Power: 1.2 W
Bearing: Sleeve
Speed: 4000 RPM
Noise: 29 dBA
Max Air: 8.79 CFM
Max Pressure: 1.46 mmH2O
Temperature: -10 to +70 C
Hours: 20000-30000
Termination: Wire leads
Weight: 20g
Impeller: Glass fibre reinforced plastic 94V-0 PBT
Frame: Glass fibre reinforced plastic 94V-0 PBT