Rockwell Automation 1761 MicroLogix 1000 Programmable Controllers - Manual (Page 102)

Preface MicroLogix 1000 Programmable Controllers User Manual
6–4
Examine if Closed (XIC)
Use the XIC instruction in your ladder program to determine if a bit is On. When
the instruction is executed, if the bit addressed is on (1), then the instruction is
evaluated as true. When the instruction is executed, if the bit addressed is off (0),
then the instruction is evaluated as false.
Bit Address State XIC Instruction
0 False
1 True
Examples of devices that turn on or off include:
•
a push button wired to an input (addressed as I1:0/4)
•
an output wired to a pilot light (addressed as O0:0/2)
•
a timer controlling a light (addressed as T4:3/DN)
Examine if Open (XIO)
Use an XIO instruction in your ladder program to determine if a bit is Off. When
the instruction is executed, if the bit addressed is off (0), then the instruction is
evaluated as true. When the instruction is executed, if the bit addressed is on (1),
then the instruction is evaluated as false.
Bit Address State XIO Instruction
0 True
1 False
Examples of devices that turn on or off include:
•
motor overload normally closed (N.C.) wired to an input (I1:0/10)
•
an output wired to a pilot light (addressed as O0:0/4)
•
a timer controlling a light (addressed as T4:3/DN)
Execution Times
(
µ
sec) when:
True False
1.54 1.72
] [
Execution Times
(
µ
sec) when:
True False
1.54 1.72
]/[