SF_Equivalent (FB)ΒΆ
FUNCTION_BLOCK SF_Equivalent
This function block converts two equivalent SAFEBOOL inputs (both NO or NC) to one SAFEBOOL output, includ-ing discrepancy time monitoring.
This function block should not be used stand-alone since it has no restart interlock. It is required to connect the output to other safety related functionalities.
Function block according to PLCopen, Technical Committee 5: Safety Software (Technical Specification), Part 1: Concepts and Function Blocks, Version 2.01 (2020-2)
- InOut:
Scope
Name
Type
Initial
Comment
Input
Activate
BOOL
FALSE
Activation of the FB.
S_ChannelA
BOOL
FALSE
Input A for logical connection.
S_ChannelB
BOOL
FALSE
Input B for logical connection.
DiscrepancyTime
TIME
TIME#0ms
Maximum monitoring time for discrepancy status of both inputs.
Output
Ready
BOOL
FALSE
Activation of the FB. TRUE indicates that the FB is activated and the outputs results are valid, FALSE the FB is not active and the program is not executed.
S_EquivalentOut
BOOL
FALSE
Safety related output
SafetyDemand
BOOL
FALSE
Output indicating that the FB is active and the primary safety function is demanded (e.g. related to the safety functionality).
Error
BOOL
FALSE
Error flag
DiagCode
WORD
0
Diagnostic register