Rockwell Automation 1752-L24BBBE SmartGuard 600 Controllers User Manual - Manual (Page 231)

Rockwell Automation Publication 1752-UM001E-EN-P - June 2014 231
Function Blocks Command Reference Appendix D
Two-hand Control Function Block Truth Table
In the truth table, 0 is off and 1 is on.
Two-hand Control Function Block Error Handling
A discrepancy error is generated when one of the inputs is not in its correct state
for longer than the discrepancy time. For example, in Dual Channel Equivalent
mode, both inputs must be active (on) within the discrepancy time or an error
occurs.
Use this table to diagnose and reset a Discrepancy Error condition in the Two-
hand Control function block.
(1) A discrepancy time check is not performed if 0 is set.
Table 21 - Truth Table for Two-hand Control Function Block
Input 1
(Pair 1 - NO)
Input 2
(Pair 1 - NC)
Input 3
(Pair 2 - NO)
Input 4
(Pair 2 - NC)
Output Enable
0 0 0 0 0
0 0 0 1 0
0 0 1 0 0
0 0 1 1 0
0 1 0 0 0
0 1 0 1 0
0 1 1 0 0
0 1 1 1 0
1 0 0 0 0
1 0 0 1 0
1 0 1 0 1
1 0 1 1 0
1 1 0 0 0
1 1 0 1 0
1 1 1 0 0
1 1 1 1 0
Table 22 - Error Detection and Reset for Two-hand Control Function Block
Error
Condition
Status When an Error Occurs To Reset the Error Condition
Output
Enable
(1)
Fault
Present
Error Output
Discrepancy
Error at Pair 1 OFF
(Safety State) ON Discrepancy
Error Pair 1: ON Remove the cause of the error and then
either:
1. Make both input pairs 1 and 2 inactive
and active again.
2. Change the controller’s operating mode
to Idle and back to Run.
Discrepancy
Error at Pair 2 Discrepancy
Error Pair 2: ON