Delta Electronics DVP15MC11T Operation Manual page 166


Users can choose different data types for the input parameter in this instruction. But the data type of
the output parameter is restricted to LREAL. An error will occur during the compiling of the software
if the data type of the output parameter is not LREAL.

Precautions for Correct Use

The input variable is not allowed to omit. An error will occur during the compiling of the software if
the input variable is omitted. But the output variable is allowed to omit.

The output value of Out is a nonnumeric value when the input value of In is a non-positive number
as shown in the following table.
The variable table and program
Variable name
LOG_EN
LOG_In
Out1

Programming Example

The data types of variables LOG_In and Out1 are INT and LREAL respectively. The value of Out1 is
0.0 if the value of LOG_In is 1 when LOG_EN changes to TRUE. The value of Out1 is 1.0 as
LOG_In is 10.

Variable 1
Variable name
LOG_EN
LOG_In
Out1

Variable 2
Variable name
LOG_EN
LOG_In
Out1

The program
Data type
BOOL
REAL
LREAL
1
L OG
L OG_E N EN ENO
LOG _In In Ou t
Data type
BOOL
INT
LREAL
Data type
BOOL
INT
LREAL
1
L OG
L OG_E N EN ENO
LOG _In In Ou t
Chapter 8 Logic Instructions
Current value
TRUE
-2.0
1.#QNAN
Out1
Current value
TRUE
1
0.0
Current value
TRUE
10
1.0
Out1
8_
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