Technical DataΒΆ
The MODBUS operating mode and the interface parameters are set in the PLC configuration: Setting COMx - MODBUS
Description of the MODBUS protocol:
| Supported standard | PM55x and PM56x: EIA RS-485 PM57x, PM58x and PM59x: EIA RS-232 / RS-485 |
| Number of connection points | 1 client Max. 1 server with RS-232 interface Max. 31 servers with RS-485 |
| Protocol | MODBUS |
| Operating mode | Client/server |
| Address | Server only |
| Data transmission control | CRC16 |
| Data transmission speed | Up to 187.500 baud |
| Encoding | 1 start bit 8 data bits 1 parity bit, (optional) even, odd, mark or space 1 or 2 stop bits |
| Max. cable length for RS-485 | 1.200 m at 19.200 baud |
If a Processor Module provides more than one serial interface, both interfaces (COM1/COM2) can be operated simultaneously as MODBUS interfaces and can operate as MODBUS server as well as MODBUS client.