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

TR_CRITICAL_IO Function Block 101* RELAY_OK := FALSE to complete initialization.* 3. Invoke repeatedly, once for each critical IO module.* 4. Read outputs CO, TMR, GE_DUAL, and GE_SINGLE for safety critical results.** In step 3, invoke with the CHASSIS and SLOT of the critical IO module,* the module application, and the relay status.* For example, if CHASSIS 1 SLOT 5 is a critical DO module with a relay,* and SCIO is the function block instance name:* SCIO( CHASSIS:=1, SLOT:= 5, APP:=RELAY, RELAY_OK:=RELAY1_OK );** Slot Number* Each logical IO slot consists of two physical slots,* a left slot and a right slot. By convention,* the physical slot number of the left slot is always odd.* The SLOT parameter is the physical slot number of the left slot.** Application* The APP parameter for a module selects the effect of a fault* on the vote mode outputs of the shutdown function blocks.* APP:=RELAY with RELAY_OK:=true* A sinlge fault (even a voter fault) degrades the mode to DUAL.* The relay provides a third channel for shutdown,* so if an output voter fails, there are still* two independent channels that can de-energize the output,* i.e., the relay and the other output voter channel.* APP:=RELAY with RELAY_OK:=false, or* APP:=DE_ENERGIZED* A voter fault degrades the mode to SINGLE.* A non-voter fault degrades the mode to DUAL.** Runtime Errors* EBADPARAM Bad parameter* CO=FALSE indicates a programming error.* See ERROR number parameter for details.*=F===============================================================================*)IF INIT THENMP( CI := TRUE ) ;CO := MP.CO ;TMR := TRUE ;GE_DUAL := TRUE ;GE_SINGLE := TRUE ;NO_VOTER_FLTS := TRUE ;ELSIF PREVIOUS_INIT THEN; (* No operation. *)ELSIF CI AND CO THENIF (DINT_TO_DWORD(SLOT) AND 1) 1 OR SLOT