Browse Prior Art Database

System-Detected Blower Fault Isolation in a Microprocessor System Environment Application

IP.com Disclosure Number: IPCOM000060251D
Original Publication Date: 1986-Mar-01
Included in the Prior Art Database: 2005-Mar-08
Document File: 2 page(s) / 45K

Publishing Venue

IBM

Related People

Rohulich, AS: AUTHOR [+4]

Abstract

Central Processing Unit designs require blowers to cool high power dissipation circuits, particularly the Central Electronic Complex where large quantities of heated air must be removed to prevent overheating and subsequent circuit stress or total destruction. The detection of a blower fault is accomplished by a design that utilizes a Hall Effect Sensor (HES). The HES 1 is mounted on the housing of a half-speed blower motor 2. The blower motor speed is monitored via HES 1. HES output pulses are fed into the 555 timer 3 and the RC time constant circuit 4. The time constant is calculated for the application of the half-speed blower 2. If an error occurs due to a defective motor, open wire, etc., the RC time constant is allowed to charge longer.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 98% of the total text.

Page 1 of 2

System-Detected Blower Fault Isolation in a Microprocessor System Environment Application

Central Processing Unit designs require blowers to cool high power dissipation circuits, particularly the Central Electronic Complex where large quantities of heated air must be removed to prevent overheating and subsequent circuit stress or total destruction. The detection of a blower fault is accomplished by a design that utilizes a Hall Effect Sensor (HES). The HES 1 is mounted on the housing of a half-speed blower motor 2. The blower motor speed is monitored via HES 1. HES output pulses are fed into the 555 timer 3 and the RC time constant circuit
4. The time constant is calculated for the application of the half-speed blower 2. If an error occurs due to a defective motor, open wire, etc., the RC time constant is allowed to charge longer. The excess charge voltage on the RC time constant circuit 4 will cause the 555 timer threshold to activate, allowing its fault output to trigger. This output sets the fault output latch 5 which is sent to a multiplexer circuit 6 where it is monitored by an 8048 microprocessor 7 along with other inputs. The fault is sampled and compared against stored data in the 8048. A non-compare indicates an error and the 8048 via an 8-bit bus sends an error code to the display unit 8 while simultaneously removing system power. The error code is then checked by the operator, and corrective action/repair is instituted.

1

Page 2 of 2

2

[This page conta...