Yokogawa RotaMASS 3-Series - Manual (Page 19)

IM 01R04B08-00E-E 1st edition February 15, 2012 -00 All Rights Reserved. Copyright © 2012, Rota Yokogawa
<5. OPERATION OF ROTAMASS 3 SERIES MODBUS COMMUNICATION TYPE>
5-1
5. OPERATION OF ROTAMASS 3 SERIES
MODBUS COMMUNICATION TYPE
5.1 Operation via display
For general information regarding the operation via display refer to the instruction manual of the standard
type IM 01R04B04-00E-E. For the Modbus communication type the operation via display is basically the
same. Extensions and restrictions are described below:
A menu has been added to Detailed Setup to configure the Modbus communication settings of ROTAMASS.
To establish communication please make sure to match the communication settings of your host system.
Due to memory restrictions the German language texts have been removed. Selection of German menu lan-
guage is therefore not possible; all texts will remain in English.
Current output 2 is not available for Modbus communication type. All menu items referring to current output 2
have therefore been removed from the display menu.
Note: due to the ability of communicating via HART and Modbus simultaneously the operation of the display
menu is slightly slower than experienced with a standard device.
5.2 Operation via HART
ROTAMASS 3 Series Modbus communication type supports also full configuration via HART communication
protocol on current output 1.
For wiring and general information regarding the operation via HART communication protocol refer to the
instruction manual of the standard type IM 01R04B04-00E-E.
Unless a special DD/DTM for the Modbus communication type is available the standard DD/DTM will be
loaded. Therefore a few restrictions apply:
1. The Modbus communication settings menu is not available via HART but only in the display menu of
ROTAMASS.
2. When changing the menu text to German, the display language will remain in English since German
language texts are not available.
3. All settings for current output 2 are visible in the standard DD/DTM. However, any settings made for
current output 2 will have no effect in the device since this output is not available.
5.3 Operation via Modbus
All ROTAMASS 3 Series Modbus communication options support reading access to all measurement values
in holding and input registers. Depending on the option configuration of selected parameters via Modbus is
also supported.
For detailed information of available parameters refer to the menu tree in chapter 6.
For configuration of selection parameters for each selection a specific value has to be written. The selection
values are found in the table in chapter 7.
Note: The Modbus communication settings of ROTAMASS can be changed via Modbus. However,
communication continues with the previous settings. The new settings will only be taken in effect after
execution of the function Modbus Init or a Power on of ROTAMASS!
Important note: Other communication protocols handle dependencies and refreshes of parameters in device
description files. In the opposite Modbus accesses only single registers (values or parameters) and the host
has usually no information about any other conditions. Furthermore according Modbus specification only few
exception codes for certain transmission errors are defined. Therefore only physical transmission is secured
by the protocol but any logical check has to be done individually by the host system. For more information
refer to chapter 8.