6 INSTALLATION AND EXTERNAL WIRING
6.4 Example of External Wiring Between the Flexible High-speed I/O Control Module and an Encoder
55
6
Example of external wiring with the SSI encoder (serial
communication)
Connect the flexible high-speed I/O control module to the SSI encoder using a shielded twisted pair cable of 0.2mm
2
or
thicker (24 AWG or larger). Make sure to check the SSI encoder specifications.
In addition, separately prepare an external power supply for the SSI encoder.
• Connect the DATA input to any of IN 0 to IN B.
• Connect the CLK output to OUT 0_DIF for SSI_Encoder_0, and to OUT 1_DIF for SSI_Encoder_1.
Relation between transmission speed and maximum cable length (reference value)
The maximum cable length described in the above is a reference value. Depending on the response performance of the SSI
encoder to be connected, the maximum cable length may become shorter than the above description because a response
delay occurs.
Therefore, check the operation using an actual encoder to be connected, and use the module.
If the cable longer than the maximum length described above is used, the module becomes following states.
• An encoder value is fixed to an incorrect value and the module does not count the value correctly.
• An encoder value fluctuates and the module does not count the value correctly.
• An encoder value cannot be read and the module does not count the value correctly.
Transmission speed
Maximum cable length
100kHz
400m
200kHz
190m
300kHz
120m
400kHz
80m
500kHz
60m
1MHz
25m
1.5MHz
10m
2MHz
5m
OUT 0_DIF+
OUT 0_DIF-
+
-
+
-
B4
A4
IO 5V
4.1k
Ω
270
Ω
240
Ω
820
Ω
IN 0_DIF
IN 0_5V
IN 0_24V
IN 0_COM
B18
A19
B19
A18
+
-
+
-
External
power
supply
Digital isolator
CLK input
SSI encoder
Flexible high-speed I/O control module
Shielded twisted pair cable
IN 0 (DATA input)
OUT 0 (CLK output)
DATA output
Summary of Contents for MELSEC-L Series LD40PD01
Page 2: ......
Page 9: ...7 MEMO ...
Page 24: ...22 2 PART NAMES MEMO ...
Page 35: ...4 PROCEDURES BEFORE OPERATION 33 4 MEMO ...
Page 263: ......