Nidec UltraFlo® cooling fans and blowers

38 x 28mm Cooling Fans for 1U Applications

W38S Vane Axial Cooling Fans

Vane axial fans in the NidecUltraFlo®W38S series deliver up to 26 CFM of forced air cooling fromsub-1U, 38mm x 28mm housings. The new fans are rated for operation at static pressure of up to 2.3 inches of water.

Models in the W38S series are available as feedback-governed, speed-stable designs or as free-running fans. Available options include an open-collector tachometer circuit (two square wave pulses per revolution, 50 percent duty cyce), an open-collector, low-pass/high-fail locked rotor alarm, and pulse-width modulated speed control circuits.

On-line documentation of the new fan series is available here:

W38S Cooling Fans

To It works to modulate the speed of the motor for thermal sensing and to modulate the current of the motor for current limiting the following method was employed.

Here we have the familiar 2 phase Unipolar driver; however, CRA and CRB have been added to allow a PWM override signal to shut the switch off.

At first glance this would appear to be elegantly simple; PWM the switch at 50% duty cycle, and © the effective voltage would appear across the winding.

Instead of 12v applied we would have 12v applied at 50% of the time giving an effective winding voltage of 6v, causing the motor to run at 1500 RPM instead of 3000 RPM.

It does not operate that way however. If this were implemented one would find the motor/fan to be operating at around 400 to 600 RPM and might have difficulty starting in the detent position.

® UltraFlo is a registered trademark of Nidec Corporation.

Contact! Home Cooling Fans Brushless DC Motors HDD Spindle Motors

Nidec three-phase brushless dc motors for plain paper copiers, laser beam printers, air moving devices, hybrid vehicle battery coolers, and automotive seat coolers. Models 58M 50M 50ML 45M and 40M outer rotor motors: Nidec motors.

White Technology Solutions, Raleigh, NC, phone 919-801-4859 or 919-870-9797, is a manufacturer's sales representative for Nidec UltraFlo cooling fans and blowers and Nidec Servo fans.

White Technology Solutions, Raleigh, NC, phone 919-801-4859 or 919-870-9797, is a manufacturer's sales representative for Nidec UltraFlo cooling fans and blowers and Nidec Servo fans.