Digitronic
Digital Cam Switch Unit
Automationsanlagen GmbH
CamCon DC16
4.3. The measuring system
The measuring system is designed to record the necessary actual values (positions) for the Cam
Switch Unit. Many different measuring system can be linked with the CamCon.
See chapter "4. Electrical connections" on page 15 and for adjustment of the measuring system to the
software of the CamCons please also consult Chapter "7.4.1. Measuring system" on page 44.
Note:
Please also consult the instruction manual for your measuring system.
4.3.1. SSI Measuring system input
Systems with a synchronous series interface = SSI. The SSI interface is widely used in industry for
absolute single and multi-turn angle encoder. At this interface the CamCon supplies the measuring
system with 24Volt. For the purpose of data reading the CamCon sends a stroke signal (clock) with
RS422 level to the measuring system. This answers synchronously with the data output of the position
in the grey code. The frequency of the pulse signal depends on the length of the cable to the
measuring system and can be set in the CamCon.
Note:
The data record corresponds to the Stegmann SSI Standard!
Clock
Data
Tp
= clock impulse
max. 1MHz to min. 66kHz.
(adjustable through the cable
length)
Tmono
= Mono flop time 25µs
CamCon
Encoder
+24V DC
0V
Clock +
Clock -
Data +
Data -
Please note:
Use a screened dual strand connection cable. Do not place
the cable parallel to a high voltage cable. If possible, lay the
screening down on both sides.
4.3.2. Parallel measuring system input
Systems with parallel 24V data leads, e.g. single turn - angle encoder or via a transformer with parallel
data output.
In this instance a gray or binary encoded value is attached to the free inputs of the CamCon and this
will be read as actual value. Since the connection cable are quite expensive and the EMV -
compatibility is limited, this interface type is rarely used in industry nowadays.
Note:
Since the outputs are partly switched parallel to the inputs in CamCon DC16, DC115,
DC300 and CamCon 1756-DICAM, these must not be programmed under any
circumstances and this reduces the number of available outputs.
Warning:
Reading a binary encoded value into the CamCon is only permitted after consultation with
the Service department of the company Digitronic.
Version: Aug. 04
Page: 20
