Owner's manual

A-9
Applications
DISCRETE OUTPUT (DO)
FUNCTION BLOCK
More information to come.
INPUT SELECTOR (ISEL)
FUNCTION BLOCK
You can use the ISEL function block to select the maximum
temperature input from four inputs and send it to a PID function block
to control a process water chiller (see Figure A-8) or you can use the
block to calculate the average temperature of the four inputs
(see Figure A-9).
Figure A-8. Input Selector Function
Block Application Example
(SEL_TYPE = max)
Figure A-9. Input Selector
Function Block Application Example
(SEL_TYPE = avg)
Figure A-10. Input Selector Function Block Application Example (SEL_TYPE = Hot Backup)
IN1 = 126 °F
IN2 = 104 °F
IN3 = 112 °F
IN4 = 130 °F
OUT = 130 °F
To Another
Function Block
SEL_TYPE = max
fieldbus-fbus_30a
Input Selector
(ISEL) Function
Block
IN1 = 126 °F
IN2 = 104 °F
IN3 = 112 °F
IN4 = 130 °F
OUT = 118 °F
To Another
Function Block
SEL_TYPE = avg
FIELDBUS-FBUS_30A
Input Selector
(ISEL) Function
Block
IN1 = 126 °F
IN2 = 104 °F
IN3 = 112 °F
IN4 = 130 °F
Input Selector
(ISEL) Function
Block
SEL_TYPE = Hot Backup
FIELDBUS-FBUS_30A
Time
IN1 IN2 Out Selected
Value Status Value Status Value Status Value Status
T
0
Good 20 Good 21 Good 20 Good 1
T
1
Bad 20 Good 21 Good 21 Good 2
T
2
Good 20 Good 21 Good 21 Good 2