Eaton EMR-3MP0 - Hardware Connection

Enter the [Device Para / Modbus / Communication / RTU] menu and set the following
communication parameters:
• »Slave ID« — the Slave-address, required to allow clear identi󰊎cation of the device.
• »Baud rate« — the Baud rate that the serial interface shall use.
Also, select the RS485 interface-related parameters such as:
• Number of data bits;
• One of the following supported communication variants:
• Number of data bits,
•
Even,
• Odd,
• Parity or no parity, or
•
Number of stop bits;
• »t-timeout«: communication errors are only identi󰊎ed after expiration of a
supervision time »t-timeout«; and
•
Response time (de󰊎ning the period within which an inquiry from the master has to
be answered).
Part 2: Hardware Connection
• For hardware connection to the control system, there is an RS485 interface at the
rear side of the device (RS485, 󰊎ber optic or terminals).
• Connect the bus and the device (wiring).
• Up to 32 devices can be connected to the bus (point to point connection/spurs).
•
Connect a terminating resistor to the bus.
Error Handling – Hardware Errors
Information on physical communication errors, such as:
• Baud rate error and
• Parity error;
can be obtained from the event recorder.
Error Handling – Errors on Protocol Level
If, for example, an invalid memory address is inquired, error codes will be returned by the
device that need to be interpreted.
114 www.eaton.com EMR-3MP0
3 Communication Protocols
3.3 Modbus®