Datasheet

215
Programmable
Controllers
CJ1W-CTS21-E
SSI Encoder Input Unit
2 independently configurable inputs for SSI-
compatible sensors
• SSI (synchronous serial interface) is a standard
communication protocol mainly used for absolute
encoders or distance measurement systems.
• It provides more flexibility, easier connection and
reduced wiring compared to parallel connection of
absolute encoders.
The Units sets up and maintains data communication with up to two SSI slave devices.
Extensive setting options allow matching the coding, baud rate or data length of any SSI device.
Function
SSI Communication
Item Specification
CLK lines Non-isolated differential line driver, RS422 compliant
DATA lines Electrically isolated differential line receiver, RS422 com-
pliant
Number of data-bits 9 to 31 (default: 24)
Value coding Gray / Binary / Tannenbaum / Raw (default: Gray)
Clock frequency 100 kHz to 1.5 MHz
Monoflop time 10 µs to 99.990 µs (default: 40 µs)
Sample rate About 2,500 Samples/sec with 2 encoders connected
(with default settings
DATA+
DATA-
CLOCK+
CLOCK-
+_ENC_PS
0V_ENC_PS
Shielded Twisted-pair Cable
SSI ENCODER CJ1W-CTS21-E
B3
A3
B2
A2
B1
A1
ENCODER
PS
B9 A9
+
-
RS422
+
-
RS422
Terminal arrangement
Item Description
Row B
Terminal no. Description
Row A
SSI DATA CH1 DATA1- B1
A1 DATA1+
SSI Clock CH1 CLOCK1- B2
A2 CLOCK1+
SSI Power Supply
OUT CH1
0V_ENC_PS B3
A3 +_ENC_PS
N.C. B4
A4 N.C.
SSI DATA CH2 DATA2- B5
A5 DATA2+
SSI Clock CH2 CLOCK2- B6
A6 CLOCK2+
SSI Power Supply
OUT CH2
0V_ENC_PS B7
A7 +_ENC_PS
N.C. B8
A8 N.C.
Encoder Power Supply
Input
0V_ENC_PS B9
A9 +_ENC_PS
Specifications
Item Classification: Special I/O Unit
CJ1W-CTS21-E
Unit numbers 0 to 94
SSI Inputs 2 Channels
SSI Configuration options
(per channel)
Baud Rate, Value coding (see above)
Resolution (9-31 bits)
Leading/trailing bits (0-31 bits)
Encoder Status bits (0-8 bits)
Parity (Odd, Even, None)
Monoflop time
CJ1W-CTS21.fm Seite 215 Mittwoch, 12. April 2006 10:14 10