Common Modbus Settings - Ametek 90B Series Installation And Configuration Manual

In addition the RS-485 termination may be enabled
The configuration application will always use the baud rate defined for the
SERIES 90B. If the baud rate is changed it will not take effect until the current
configuration session is complete.

Common Modbus Settings

Modbus Address
In master mode, this is the address of the slave annunciator that the master will
connect to. In slave mode this address is the annunciators own local Modbus
address. Every system on a common serial bus must be given a unique address.
Valid addresses are from 1 to 255.
Receive & Transmit Start Address
This defines the base register address for sending and receiving information.
Advisory
In some systems it may be necessary to separate the receive and transmit
registers by address to avoid overwrites. When operating in modbus master
mode the system will alternately transmit (FN16) and receive (FN03) register
data at approximately 0.5sec intervals. In some systems point data may be
overwritten before it can be forwarded if receive and transmit registers are the
same. In this case it is suggested that separate transmit and receive registers are
used e.g. 40001 and 40017.
Modbus Mode
The Modbus Mode may be selected from:-
Master
Slave
A Master unit may issue command functions and a slave unit responds to them.
When the SERIES 90B configuration application is being used the SERIES 90B
will be in slave mode independent of its Mode setting.
84 Series 90B