Scan List; Basic Settings; Network Settings; Communication - GE D485 Instruction Manual

Modbus to devicenet

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COMMUNICATION MODEL

SCAN LIST

NOTE

5–2

The D485 uses pre-configured Modbus RTU commands, acting as a Modbus RTU master.

With Modbus RTU, each transaction is substituted with a pre-defined command that can

be selected from a list of available commands.

It is still possible, though, to define custom message frames by creating a transaction

instead of selecting a pre-defined command. A command is actually a transaction that

has been defined in advance and stored in a list.

Once the configuration has been downloaded to the D485, the D485 firmware searches

the scan-list, using the defined transactions for communication with the slave-devices.

Each node in the scan-list represents a slave device on the Modbus network. In EnerVista

P485/D485 Setup, each node is given a specific name and assigned an address in standard

Modbus RTU commands. The address must match the internal setting on the slave device.

Select 'Modbus Network' in the Navigation window to gain access to basic settings in the

Parameter window.

Refer to Serial interface settings on page 4–13 for details.

The message delimiter value is the minimum time in steps of 10 ms separating the

messages. According to the Modbus specification, the message delimiter has a default

setting of 3.5 characters.If this value is set to "0", the D485 will use the Modbus standard

3.5 character message delimiter. The time in milliseconds is then dependent on the

selected baud rate, but this is all handled by the D485.

Due to its impact on subnet functionality, use caution when changing this parameter.

Figure 5-2: D485 scan list

Figure 5-3: Parameter window

D485 MODBUS TO DEVICENET CONVERTER – USER GUIDE

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