Type ConversionBeginnerIEC 61131-3

BOOL_TO_INT (Boolean to Integer Conversion)

Converts FALSE to 0 and TRUE to 1 for numeric operations.

The BOOL_TO_INT function converts a boolean value to an integer: FALSE becomes 0 and TRUE becomes 1. This conversion is useful for accumulating boolean conditions into numeric values, creating status codes from individual bits, and using boolean signals in arithmetic calculations.

Parameters

Inputs

Name	Type	Description
IN	BOOL	Boolean value to convert

Outputs

Name	Type	Description
OUT	INT	0 for FALSE, 1 for TRUE

Structured Text Example

// Count active sensors
Active_Count := BOOL_TO_INT(Sensor_1) + BOOL_TO_INT(Sensor_2) 
               + BOOL_TO_INT(Sensor_3) + BOOL_TO_INT(Sensor_4);

// Use boolean as multiplier
Output := Base_Value * BOOL_TO_INT(Enable);

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Platform-Specific Implementation

Siemens (TIA Portal)

Use CONVERT instruction or BOOL_TO_INT in SCL.

Allen-Bradley (Studio 5000)

Implicit in most contexts; boolean contacts evaluate to 0/1.

CODESYS

Use BOOL_TO_INT() function in ST.

Common Applications

Counting active conditions
Status code construction
Conditional arithmetic
Boolean to numeric conversion for HMI
Weighted voting systems

Frequently Asked Questions

What is BOOL_TO_INT (Boolean to Integer Conversion) in PLC programming?

Converts FALSE to 0 and TRUE to 1 for numeric operations. The BOOL_TO_INT function converts a boolean value to an integer: FALSE becomes 0 and TRUE becomes 1. This conversion is useful for accumulating boolean conditions into numeric values, creating status codes from individual bits, and using boolean signals in arithmetic calculations.

What are common applications of BOOL_TO_INT (Boolean to Integer Conversion)?

BOOL_TO_INT (Boolean to Integer Conversion) is commonly used for: Counting active conditions, Status code construction, Conditional arithmetic, Boolean to numeric conversion for HMI, Weighted voting systems.

How do I use BOOL_TO_INT (Boolean to Integer Conversion) in different PLC platforms?

Siemens: Use CONVERT instruction or BOOL_TO_INT in SCL. Allen-Bradley: Implicit in most contexts; boolean contacts evaluate to 0/1. CODESYS: Use BOOL_TO_INT() function in ST.