Browse Prior Art Database

A Fail Safe Scheme for Thermally Protecting Data Storage Library

IP.com Disclosure Number: IPCOM000110222D
Original Publication Date: 1992-Oct-01
Included in the Prior Art Database: 2005-Mar-25
Document File: 1 page(s) / 62K

Publishing Venue

IBM

Related People

Dimitri, KE: AUTHOR [+2]

Abstract

Disclosed is a scheme that ensures that a fan-sensing circuit is properly powered up and connected.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 68% of the total text.

A Fail Safe Scheme for Thermally Protecting Data Storage Library

      Disclosed is a scheme that ensures that a fan-sensing circuit
is properly powered up and connected.

      The main components in an optical library include optical
drives, autochanger controller and cooling fans, all powered by a
single power supply.  The host processor usually has its own power
supply.

      This disclosure describes an optical library in which the Host
processor has its own power supply (see Figure 1).  In this
disclosure a fan detect-sensing circuit is added to the optical
library (see Figure 2).  The fan-detecting circuit monitors each of
the fans RPM via their HALL effect signal output.

      If the fan RPM is too low, then the fan-sensing circuit will
shut down the power supply by opening the normally closed relay
contact points.  Opening these relay points disconnects the power
supply sense circuitry from ground.  This, in turn, shuts off the
power supply.  Turning off the power supply removes power from the
optical drives and prevents permanent thermal damage and/or
accelerated aging to the media that is left in the drive.  The power
supply will not repower up by itself until its own AC power is
removed and reset via the operator ON/OFF switch.

      The DC voltages needed by the autochanger controller card and
the fans are supplied from the fan sense circuit card; the voltages
needed by the fan sense circuit card are supplied by the power supply
an...