Galvanic Applied Sciences 943-TGX-CE, Operation Manual

Page: 90 / 151

Revision 4 90 April 2020
Table 25: Modbus Communication Parameters
Parameter Explanation
IP Port Number
Port number to be used if the communication protocol being
used is Modbus TCP/IP.
Modbus Address
Modbus address of the analyzer. This address needs to be
entered into the DCS to allow the DCS to communicate
correctly with the analyzer.
32 Bit Register Swap
If register swap is selected, the portion of the 32-bit register
that follows the decimal point is transmitted in the first 16-bit
word, and the portion that precedes the decimal point is
transmitted in the second 16-bit word. If register swap is not
selected, the portion that precedes the decimal point is
transmitted first.
NOTE: Only used if Modicon-32 format is chosen
Mode
Sets the mode for beginning and ending messages. ASCII
mode uses ASCII characters to mark the beginning and
ending of messages, whereas
RTU uses time gaps to mark
the beginning and ending of messages. Choice will depend
on the DCS being used.
Endian
Selects between Big Endian and Little Endian . In Big
Endian, the most significant bit is transmitted first, whereas
in Little Endian, the least significant bit is transmitted first.
Note: Only used if Modicon-32 format is chosen
Baud Rate
Selects the Baud Rate to be used for communication
between the analyzer and the DCS. Usually 9600 but may
differ depending on the DCS being used.
Note: Only used if RS485 serial communication is used
for Modbus
Data Bits
Number of data bits transmitted at a time. Usually 8, but 7
may be used under some circumstances
Note: Only used if RS485 serial communication is used
for Modbus
Parity
Type of parity checking used for data transmission. Usually
None , but Even or Odd may be used under some
circumstances.
Note: Only used if RS485 serial communication is used
for Modbus
Stop Bits
Number of bits marking the end of a transmitted byte. Usually
1 but may be 2 under some circumstances.
Note: Only used if RS485 serial communication is used
for Modbus
The various items in the Available Points listing on the left side of the Modbus page can be
accessed by clicking on the + sign. The items in this listing can be used to populate the
Modbus Items list on the right side of the Modbus page by dragging and dropping them into
the Modbus list. The general types of data in each folder in the Available Points list is given
in Table 26.