Safety Considerations Guide, Tricon v9.0 - Tuv-fs.com

96 TR_CRITICAL_IO Function BlockTR_CRITICAL_IO Function BlockAccumulates Status of Critical I/O ModulesThe TR_CRITICAL_IO function block provides an easy way to accumulate thestatus of all safety-critical I/O modules in a Tricon system.Instructions for UseThe following instructions for using the TR_CRITICAL_IO function block applyto the Structured Text (ST) language.▼To obtain the accumulated status of critical I/O modules:1 Initialize TR_CRITICAL_IO by invoking it once with INIT := TRUE.SCIO( INIT := TRUE );where SCIO is the function block instance name2 To complete initialization, invoke TR_CRITICAL_IO again as follows:SCIO( INIT := FALSE, CI := TRUE, APP:=DE_ENERGIZED, RELAY_OK:=FALSE );where SCIO is the function block instance name3 To get the status of all safety-critical I/O modules, invoke each module byspecifying these input values:• CHASSIS• SLOT• APP• RELAY_OKIf CHASSIS 1 SLOT 1 is a critical DI module, and CHASSIS 1 SLOT 2 is acritical DO module with a relay, then the following example applies. SCIO isthe function block instance name:SCIO(CHASSIS:=1,SLOT:=1,APP:=DE-ENERGIZED,RELAY_OK:=FALSE);SCIO(CHASSIS:=1,SLOT:=2,APP:=RELAY,RELAY_OK:=RELAY1_OK);Tricon Safety Considerations Guide