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Air Cooled Data Processor With Blower Motor Controlled by Variable Frequency Source to Reduce Noise When Cooling Load is Low

IP.com Disclosure Number: IPCOM000060113D
Original Publication Date: 1986-Feb-01
Included in the Prior Art Database: 2005-Mar-08
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Maling, GC: AUTHOR [+2]

Abstract

In this data processor, the blowers for air cooling have sufficient capacity for adverse conditions of temperature, coo load, and altitude, as is conventional, and it also has a variable frequency digital control that controls the frequency of the power which drives the blower motors. The motors operate at the minimum speed that produces adequate cooling. Preferably, the control converts a commercial power supply of 50 or 60 hertz to power the blowers in a range of 47 to 63 hertz. Therefore, when the blowers are providing just adequate cooling, the motor speed corresponds to an input frequency of 47 hertz. Under adverse conditions, the motor speed can increase to 63 hertz. The normal operating condition therefore produces a noise level which is approximately 6 decibels below the extreme condition which is rare.

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Air Cooled Data Processor With Blower Motor Controlled by Variable Frequency Source to Reduce Noise When Cooling Load is Low

In this data processor, the blowers for air cooling have sufficient capacity for adverse conditions of temperature, coo load, and altitude, as is conventional, and it also has a variable frequency digital control that controls the frequency of the power which drives the blower motors. The motors operate at the minimum speed that produces adequate cooling. Preferably, the control converts a commercial power supply of 50 or 60 hertz to power the blowers in a range of 47 to 63 hertz. Therefore, when the blowers are providing just adequate cooling, the motor speed corresponds to an input frequency of 47 hertz. Under adverse conditions, the motor speed can increase to 63 hertz. The normal operating condition therefore produces a noise level which is approximately 6 decibels below the extreme condition which is rare. The noise level in the installation is therefore reduced for normal operating conditions. The power supply frequency is controlled by a digital oscillator which is in turn controlled by a power-thermal control system or by a digital computer. The control system or computer receives temperature signals from either inside the processor or from locations in the computer installation, and instructs the digital oscillator to produce the appropriate power line frequency to drive the blowers. If the control system fails, the blower motors c...