Browse Prior Art Database

Uninterruptable Power Source

IP.com Disclosure Number: IPCOM000083483D
Original Publication Date: 1975-Jun-01
Included in the Prior Art Database: 2005-Mar-01
Document File: 3 page(s) / 39K

Publishing Venue

IBM

Related People

Chorpenning, JS: AUTHOR

Abstract

In the powering of data processing systems having volatile storage devices, it is necessary to avoid an abrupt loss of power due to an outage of the primary power source. An auxiliary power source is usually provided and will have sufficient battery power to maintain operations for a time, or at least long enough for an orderly shutdown. However, the auxiliary supply should not be switched in when the main power goes out if there is no power being used, i.e., the processor is not in operation, and for this purpose, a current sensor in the power supply output is used to control the auxiliary power supply.

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 53% of the total text.

Page 1 of 3

Uninterruptable Power Source

In the powering of data processing systems having volatile storage devices, it is necessary to avoid an abrupt loss of power due to an outage of the primary power source. An auxiliary power source is usually provided and will have sufficient battery power to maintain operations for a time, or at least long enough for an orderly shutdown. However, the auxiliary supply should not be switched in when the main power goes out if there is no power being used, i.e., the processor is not in operation, and for this purpose, a current sensor in the power supply output is used to control the auxiliary power supply.

This control is especially desirable when substantial energy is dissipated in the auxiliary power supply just to maintain it in a power available condition, as in a switching transistor inverter supply to provide auxiliary AC. When the auxiliary power supply is battery powered, this provision will lengthen the life of the expensive batteries by eliminating unnecessary ones of the charge and discharge cycles which reduce battery life.

As indicated on the drawing, an AC power line 1 is connected through a manually controlled switch SW1 to the coil 2 of an AC sense relay K, which will be energized so long as the AC voltage is at least 80% of normal. The AC line is also connected to a transformer winding 3 and to a rectifier unit 4, which will rectify the AC to provide DC output power to a load 5. A current sensor 6 is in the power line to rectifier 4 and will send an output signal to an auxiliary AC control 7, to indicate when current is being supplied to the load 5.

Auxiliary AC power is supplied by an inverter supply comprising a generator 8, which may be connected through contacts 9 and 10 to a secondary winding 11 on the same transformer as winding 3. A battery 12 will power generator 8 whenever a switch 14 is closed at the time switches 9 and 10 are operated. Another set of switch contacts SW2 is closed when an AC power swi...