Siemens SIMATIC S7-300 Module data Reference Manual

Special Signal modules
5-12
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
Example of normalization of an encoder value
You are using a single-turn encoder with 2
9
units= 512 units/ revolution
(resolution/360°).
In STEP 7 you have set the following parameters:
• Absolute encoder: 13 bits
• Normalization: 4 places
• Units / revolution: 512
Before the normalization: cyclically acquired encoder values 100
0
31
0000 00000000 0000000000000
XXXX
00100
11
0000
Transferred bits
Relevant bits
After the normalization: encoder values 100
0
31
0000 00000000 0000000000000 001001100000000
Relevant bits
Double data word
Double data word
Result: Bits 0 to 3 (4 places, marked with “x”) are omitted.
5.4.7 Freeze Function
The freeze function “freezes” the current encoder values of the SM 338. The
freeze function is coupled to the digital inputs DI 0 and DI 1 of the SM 338.
The freeze is triggered by an edge change (rising edge) on DI 0 or DI 1. A frozen
encoder value is identified by the bit 31 (output address) being set. With a digital
input you can freeze one, two or three encoder values.
You must switch on the freeze function, i.e. set the corresponding parameters in
STEP 7 .
The encoder values are retained until the freeze function is ended and can thus be
evaluated dependent on the event.

Siemens SIMATIC S7-300 Module data Specifications

General

Series	S7-300
Manufacturer	Siemens
Protection Class	IP20
System	SIMATIC S7-300
Digital Inputs	Varies by module
Digital Outputs	Varies by module
Analog Inputs	Varies by module
Analog Outputs	Varies by module
Central Processing Unit	Varies by CPU model
Supply Voltage	24V DC or 120/230V AC
CPU Type	Varies (e.g., CPU 312, CPU 315, etc.)
Memory	Varies by CPU model
Communication Interfaces	MPI, PROFIBUS
Programming Languages	LAD, FBD, STL, SCL, GRAPH
Operating Temperature	0°C to 60°C
Storage Temperature	-40°C to 70°C
Relative Humidity	10% to 95% (non-condensing)