GE GFK-0787B user manual Voting with Two Discrete Inputs

4

Voting with Two Discrete Inputs

Two inputs may be present in either a Duplex input group, or in a Triplex input group where one of the three inputs has failed.

For its 2 out of 3 voting, the GMR software uses the group's configured Duplex State in place of a third actual input.

		Field Input Data		Single Input Provided
Field Input		Input A	0	to Application Logic
		Input B	1		1
Data
		Input C	1	GMR Software Performs
				2 out of 3 Voting
	Duplex State		1

Default State

0

Discrete Input Voting with Two Inputs Present and Duplex State Set to 1

If the Duplex State is set to 1 and two inputs are available, both of the ªactualº inputs must be 0 for the voted input state to be 0. The voted input is 1 if either of the actual inputs is 1.

InputA State	Input B State	InputC	VotedInputState
		(Duplex State)
0	0	1	0
0	0	1	0
0	1	1	1
0	1	1	1
1	0	1	1
1	0	1	1
1	1	1	1
1	1	1	1

Discrete Input Voting with Two Inputs Present and Duplex State Set to 0

If the Duplex Default state is set to 0 and two inputs are available, both of the ªactualº inputs must be 1 for the voted input to be 1. The voted input is 0 if either of the remaining inputs is 0.

		InputA State	Input B State	InputC	VotedInputState
				(Duplex State)
		0	0	0		0
		0	0	0		0
		0	1	0		0
		0	1	0		0
		1	0	0		0
		1	0	0		0
		1	1	0		1
		1	1	0		1
4-10	GeniustModular Redundancy Flexible Triple Modular Redundant (TMR) System					GFK-0787B
	User's Manual ± March 1995