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Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) User Manual

Page 162

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Chapter 9
Using Comparison Instructions

9–11

True/False Status of the Instruction

If the Low Limit has a value equal to or less than the High Limit, the
instruction is true when the Test value is between the limits or is equal to
either limit. If the Test value is outside the limits, the instruction is false, as
shown below.

Example, low limit less than high limit:

Low

Limit

High

Limit

Instruction is True

when Test value is

Instruction is False

when Test value is

5

8

5 through 8

–32,768 through 4 and 9 through 32,767

False

True

False

–32,768

Low Limit

High Limit

+ 32,767

If the Low Limit has a value greater than the High Limit, the instruction is
false when the Test value is between the limits. If the Test value is equal to
either limit or outside the limits, the instruction is true, as shown below.

8

5

–32,768 through 5 and 8 through 32,767

6 and 7

Example, low limit greater than high limit:

Low

Limit

High

Limit

Instruction is True

when Test value is

Instruction is False

when Test value is

True

False

True

–32,768

High Limit

Low Limit

+ 32,767