Pepperl+Fuchs WCS Series User Manual

WCS* Read Head Position Encoding System
SSI Interface (LS3xx*)
2020-01
31
Data cable
For SSI data transfer, a 6-wire, shielded, twisted pair data cable (3 x 2) is used. One wire pair is
used for the supply voltage, one pair for the CLK line, and one pair for the DATA line. The cable
lengths that are technically possible can be determined from the tables. For large cable lengths
(longer than 12 m) between the SSI read head and control panel, we recommend using the SSI
interface module. In this case, the data is transferred asynchronously from the read head to the
interface module via the RS-485 interface. The data is converted to SSI protocol immediately
next to the control panel. The table below shows the possible cable lengths depending on the
cable capacitance (core-core). The number of connected read heads is of no significance.
Capacitance
(core-core)
SSI Interface
125 kHz 250 kHz 500 kHz
60 pF 200 m 100 m 30 m
90 pF 150 m 80 m 25 m
120 pF 100 m 60 m 20 m

Pepperl+Fuchs WCS Series Specifications

General

Brand	Pepperl+Fuchs
Model	WCS Series
Category	Media Converter
Language	English