Patent №
US 4,752,869
Granted
1988-06-21
Filed 1985
Owner
—
Lab
—
AI components
1
planning
Assignment
None on record
Dataset
AIPD
2023_r1 edition
Application
06732325
Redundant trip logic microprocessors produce partial trip signals which are voted on by a pair of voters at the power interface to the actuated devices. The logic implemented by each trip logic processor is straight-forward and can be designed for each individual plant. Also included is an automatic tester and testing method which can confirm the accuracy of A/D converters, digital inputs, check the trip points of bistable, verify all the trip and voting logic, and measure the time response of each channel. The test subsystem uses a microcomputer to control the isolation of the analog field sensor signals and digital contact signals from the analog and digital inputs, control the generation and/or injection of various combinations of reference and test signals, and monitor the response of the trip logic processors and voter to the test signals.