Other signal modules
Signal modules
This chapter describes the technical data and properties of the S7-300 signal modules.
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
Number of in-
puts/outputs
Suitable for...
Isochronous mode
supported
Programmable diag-
nostics
Diagnostics interrupt
Special features
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
Simulator module SM 374;
IN/OUT 16
•
max. 16 inputs or outputs
Simulation of:
•
16 inputs or
•
16 outputs or
•
8 inputs and 8 outputs
no
no
no
Function adjustable with
screwdriver
Dummy module DM 370
1 slot reserved for non-
programmable module
Dummy for:
•
Interface modules
•
non-programmable signal
modules
•
modules which occupy 2
slots
no
no
no
the mechanical structure and
addressing of the overall con-
figuration remains unchanged
when DM 370 is replaced with
a different module.
7
Position decoder module
SM 338; POS-INPUT
•
3 inputs for absolute en-
coders (SSI)
•
2 digital inputs for freezing
encoder values
Position detection using up to
three absolute encoders (SSI)
Encoder types: Absolute en-
coder (SSI), message frame
length 13 bits, 21 bits or 25 bits
Data formats: Gray code or
binary code
yes
no
programmable
SM 338 does not support ab-
solute encoders with a mon-
oflop time > 64 µs
493