S7-300 Automation System Module data
Manual, 08/2006, A5E00105505-04
7-1
Other signal modules
7
Signal modules
This chapter describes the technical data and properties of the S7-300 signal modules.
7.1 7.1 Module overview
Introduction
The table below summarizes the essential features of the signal modules described in this
chapter. This overview supports you in selecting a module to suit your requirements.
Table 7-1 Special signal modules: Overview of properties
Properties Simulator module SM 374;
IN/OUT 16
Dummy module DM 370 Position decoder module
SM 338; POS-INPUT
Number of
inputs/outputs
• max. 16 inputs or outputs
1 slot reserved for one non-
programmed module
• 3 inputs for the connection
of absolute value encoders
(SSI)
• 2 digital inputs for freezing
encoder values
Suitable for... Simulation of:
• 16 inputs or
• 16 outputs or
• 8 inputs and 8 outputs
Dummy for:
• Interface modules
• non-programmed signal
modules
• Modules which occupy 2
slots
Position detection with up to 3
absolute value encoders (SSI)
Encoder types: Absolute value
encoder (SSI) with 13-bit, 21-
bit or 25-bit frame lengths
Data format: Gray code or
binary code
Isochronous mode
supported
No No Yes
Programmable
diagnostics
No No No
Diagnostic interrupt No No adjustable
Special features Function adjustable with
screwdriver
When replacing DM 370 with
another module, the
mechanical assembly and
address
assignment/addressing of the
entire system remain
unchanged
SM 338 does not support
absolute value encoders with a
monoflop time greater than 64
ms