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All necessary components are installed with PVI Setup.
Serial communication can be operated as a point-to-point connection (RS232/RS422) or as a network connection (RS485).
For RS485 operation, take note that active/passive switching of the RS485 interface can take up to 15msec in Windows NT and up to 10msec in Windows 95. This can cause a bus collision with a PLC response. Setting the idle time on the PLC can delay the response frame by the required time. The idle time is specified in characters when NET2000 is initialized.
Example: NET2000.mode = "RS485,19200,I=100"
Since the response frame requires a minimum of 10 ms because it runs in the PLC task class (NET2000.task_class=1), the difference can be determined with the idle time (1 character corresponds to: 1/baud rate * 11 bits).
Executed as an RS485 twisted pair cable, shielded. Cross-section: min. 0.5 mm². Wave impedance: 120 ohms. Terminating resistor: 120 ohms on both ends. Length: maximum 1,200 meters. Maximum line resistance: 50 ohms per wire.
The cabling for the RS485 network can only be made using a bus structure. The bus connection can be made either directly or using a maximum 0,25 m long branch line.