The programmable logic controller has several converter instructions. Let’s study * converter instructions in the Siemens PLC programming*.

Till now you can see the various instructions of the PLC like **Logic Gates, Bit Logic Instructions, 20+ Arithmetic instructions, PLC Timers and PLC Counters, etc.**

There are 15 converter instructions you can find while programming. Let’s study each of these instructions in detail.

Table of Contents

**Converter Instructions in PLC Programming**

**Integer to BCD conversion**

This instruction converts the integer value into a three-digit Binary Coded Decimal value. It can convert integer value into BCD up to +/- 999.

**Double Integer to BCD Conversion**

This instruction converts the double integer value into a seven-digit Binary Coded Decimal value. It can convert double integer value into BCD up to +/- 9999999.

**BCD to Integer Conversion**

This instruction converts a three-digit Binary Coded Decimal value into an integer value.

**BCD to Double Integer Conversion**

This instruction converts a seven-digit Binary Coded Decimal value into a double integer value.

**Integer to Double Integer Conversion**

This instruction converts an integer value(16-bit) in double integer value(32-bit). The input parameter is a single word while the output parameter is the double word here.

**Double Integer to Real Conversion**

This instruction converts a double integer value into a floating-point number.

**Invert Integer(One’s Complement of Integer)**

This instruction does the one’s complement with the 16-bit integer value and gives the output. Here both the input and output values are 16-bit.

**Invert Double Integer(One’s Complement of Double Integer)**

This instruction does the one’s complement with the 32-bit integer value and gives the output. Here both the input and output values are 32-bit.

**Negative Integer(Two’s Complement of Integer)**

This instruction does the two’s complement with the 16-bit integer value and gives the output. Here both the input and output values are 16-bit.

**Negative Double Integer(Two’s Complement of Double Integer)**

This instruction does the two’s complement with the 32-bit integer value and gives the output. Here both the input and output values are 32-bit.

**Negative Real**

This instruction multiplies the input floating-point number by -1 and gives the output. The input and output both here are floating-point numbers.

**ROUND**

This instruction reads the input value as a floating-point number and converts it into a 32-bit double integer value. **The result is the nearest integer number.**

**TRUNC**

This instruction reads the input value as a floating-point number and converts it into a 32-bit double integer value. **The result is the nearest integer number to zero.**

**CEIL**

This instruction reads the input value as a floating-point number and converts it into a 32-bit double integer value. **The result is the nearest integer number to the + infinity.**

**FLOOR**

This instruction reads the input value as a floating-point number and converts it into a 32-bit double integer value. **The result is the nearest integer number to the – infinity.**

**Summary**

These are all the converter instructions in PLC. Please feel free to give your feedback in the comment section below. You can also find my previous tutorial about the plc programming instructions.

**⇒ What is PLC? How does it work?**

**⇒ Logic gates using PLC ladder logic.**

**⇒ Basic bit logic instructions with PLC programming examples.**

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**⇒ 30+ Most useful PLC communication protocols**

**You can also find the important questions and answers asked in the interview.**

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