Browse Prior Art Database

Testing Electromagnetic Switching Devices

IP.com Disclosure Number: IPCOM000094323D
Original Publication Date: 1966-Sep-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 2 page(s) / 27K

Publishing Venue

IBM

Related People

Heilweil, MF: AUTHOR [+2]

Abstract

This apparatus provides circuitry for testing switching devices to determine failures of contacts to either open or close.

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Testing Electromagnetic Switching Devices

This apparatus provides circuitry for testing switching devices to determine failures of contacts to either open or close.

Positive going pulses are provided on line 10 which controls the operation of to be tested switch RS and of Nor's 14. An additional circuit, not shown, is provided generating a positive level on line 15 when switch RS is closed.

Under normal operating conditions with both lines 10 and 15 down and with latch 30 reset, output 38 is at a positive level and output 40 at a zero level. Both outputs 69 and 70 are at zero level.

At the beginning of an input pulse on line 10 and before the closing of the switch RS, latch 30 is set, output 38 becomes low and output 40 positive. Nevertheless outputs 69 and 70 remain at zero level. When the switch RS closes before the end of the input pulse, latch 30 is reset. Outputs 69 and 70 still remain at zero level.

Should RS fail to close before the end of the pulse, when the level on 10 falls to zero, all three inputs to Nor 16 are at zero level, giving a positive level on 69. This indicates a faulty operation of the switch RS.

Should the switch fail to open before the beginning of the next input pulse when the level on line 10 rises, all three inputs to Nor 18 are at zero level, giving a positive level on 70. This indicates another faulty operation of switch RS.

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