Counting With The Fm - Siemens SIMATIC S7-400 Configuration And Use Manual

4.3

Counting with the FM 450-1

Introduction
You can use the intelligent counter module, FM 450-1, for a wide range of
high-frequency counting tasks. It provides the following features to relieve the load
on the CPU:
• Direct evaluation of the signals from incremental encoders
• Direct evaluation of gate signals such as those from photoelectric barriers via
integrated digital inputs
• Comparison operations and response output via integrated digital outputs
Counter functions of the FM 450-1
The FM 450-1 provides you with the following counter functions:
• Continuous counting
• Single counting
• Periodic counting
Performance Characteristics of the FM 450-1
The FM 450-1 has the following performance characteristics:
• Maximum counting frequency
-- 500 kHz with 5 V encoders
-- 200 kHz with 24 V encoders
• Maximum counting width
-- 32 bit
• Connectable encoders
-- 5-V incremental encoder with RS 422 interface
-- 24 V incremental encoder
-- 24 V directional encoder
-- 24 V pulse generator
Automation System S7-400 Configuration and Use
A5E00442711-02
Technological Functions of the S7-400
4-5