Emerson Process Management 1500 manual 6.12.2Changing the Modbus address

Optional Transmitter Configuration

Table 6-6Digital communications fault indicators and values continued

Fault indicator options	Fault output value
Not-A-Number (NAN)	Process variables report IEEE NAN and Modbus scaled integers report Max Int.
	Totalizers stop counting.
Flow to Zero	Flow rates go to the value that represents zero flow; other process variables are not
	affected. Totalizers stop counting.
None (default)	Process variables reported as measured.

6.12.2Changing the Modbus address

The transmitter’s Modbus address is used by devices on a network to identify and communicate with the transmitter using Modbus protocol. The Modbus address must be unique on the network. If the transmitter will not be accessed using Modbus protocol, the Modbus address is not required.

Modbus addresses must be in the range 1–110, inclusive.

If you are connected to the transmitter using an RS-485 connection, and you change the Modbus address, then:

•If you are using ProLink II, ProLink II will automatically switch to the new address and retain the connection.

•If you are using a different host program, the connection will be broken. You must reconnect using the new Modbus address.

Note: Changing the Modbus address does not affect service port connections. Service port connections always use a default address of 111.

6.12.3Changing the RS-485 parameters

RS-485 parameters control how the transmitter will communicate over its RS-485 terminals. The following parameters can be set:

•Protocol

•Baud rate

•Parity

•Stop bits

To enable RS-485 communications with the transmitter from a remote device:

1.Set the transmitter’s digital communications parameters appropriately for your network.

2.Configure the remote device to use the specified parameters.

If you are connected to the transmitter using an RS-485 connection:

•And you change the the baud rate:

-If you are using ProLink II, ProLink II will automatically switch to the new baud rate and retain the connection.

-If you are using a different host program, the connection will be broken. You must reconnect using the new baud rate.

•And you change the protocol, parity or stop bits, all host programs will lose the connection. You must reconnect using the new settings.

Note: Changing the RS-485 communication settings does not affect service port connections. Service port connections always use default settings.

50 Micro Motion® Model 1500 Transmitters with the Filling and Dosing Application