The FM 450-1 intelligent counter module is an outstanding choice for a wide variety of high-frequency counting tasks up to 500 kHz. It has two counting channels, one for up counting and one for down counting.

The FM 450-1 acquires the pulses from incremental encoders in dependence on gate signals. It evaluates the direction of the pulses and compares the counter value with two programmable comparison values.   

The FM 451 is a positioning module for adjusting and positioning mechanical drives on the basis of the rapid traverse/creep speed principle.
The FM 451 is used in the SIMATIC S7-400. The module makes it possible to position three axes independently of one another. The axes in question may be linear axes with limited traversing range or continuously rotating rotary axes.
Incremental encoders and SSI encoders can be used for position decoding.

The FM 452 electronic cam controller is a 1-channel module for the solution of position-dependent or time-dependent tasks.
The FM 452 is far superior to mechanical cam controllers, due particularly to its high level of flexibility.
An incremental encoder, an SSI encoder or a 24 V initiator can be connected to the module.

The 3-channel FM 453 positioning module is suitable for a broad spectrum of positioning tasks with stepper and servo motors.
Rotary and linear axes can be traversed absolutely or relatively.
The module can be used for simple point-to-point positioning tasks as well as for complex traverse profiles with the highest demands for dynamic response, accuracy, and velocity through to multi-axis applications.
Application examples include positioning infeed axes, positioning axes, setup axes, operating axes, production axes, and transport axes.

Autonomous positioning of the stepper and servo motors takes the load off the CPU of the automation system.
FM STEPDRIVE and SIMOSTEP stepper motors perfectly complement stepper motor axes. The same applies for servo motor axes with SIMODRIVE 611 Universal or MASTERDRIVES MC/VC and 1FT6-/1FK6-/1FK7 servo motors.   

The main functions performed by stepper and servo motors include:

• Automatic mode:     
  Execution of complex positioning profiles (traverse programs) continuously or also step by step. The traverse programs can be loaded during operation

• MDI/MDI on-the-fly   

• Jog/setup

Within the SIMATIC S7-400, the enhanced application module FM 458-1 DP is setting new standards. This intelligent module combines powerful arithmetic operations ability, high processing speed, precision and flexibility. These are the features required to solve a wide range of processing tasks universally even with extremely high throughput rates

For you this means: even more flexibility and economic viability in implementing sophisticated PLC, motion control and processing tasks.

Communication
Communication takes place over the PROFIBUS DP interface on the FM 458-1 DP. This offers the following characteristics:

• Constant bus cycle time, i.e. the PROFIBUS DP cycle is always precisely the same length.

• Isochronous, i.e. the CPU, I/O and user program are synchronized with the PROFIBUS cycle.

• Slave-to-slave communication, i.e. the configured slaves can exchange data with each other directly without the need for any additional configuring work on the FM 458-1 DP.

• Routing capability, i.e. all nodes are accessed over one interface, e.g. MPI (Multi-Point Interface) or PROFIBUS DP and optionally also Industrial Ethernet.

Up to 100 drives of the SIMOVERT Masterdrives series or SIMOREG series can be connected per ring over the highspeed, fiber-optic SIMOLINK connection.