Yokogawa Removable Chassis DX1000N - Manual (Page 248)

App-1
IM 04L41B01-17E
Appendix
1
2
3
4
5
6
App
Index
Appendix 1 Data Dropout during Modbus
Communication
Data Dropout during Modbus Client
If the response to the previous command is not complete when the DX attempts to issue
a command to a server device, the DX command cannot issue the command causing a
data dropout. Take appropriate measures by referring to the following figures.
Read cycle
Data dropout
(Servers 2 and 3)
Data dropout
(Server 3)
Server device 1
Server device 2
Server device 3
G
G
G
G
G
G
Read cycle
(Retry)
: Status lamp
: Response from the server device
: Command from the DX
Data dropout
(Servers 2 and 3)
Server device 1
Server device 2
Server device 3
Read cycle
Timeout value
Connection dropped
Data dropout
(Servers 2 and 3)
Server device 1
Server device 2
Server device 3
G G
G
G
G
G G
O
Connection dropped Connection recovered
Timeout value
G
G
G
G
O
Y
Connection retry time*
G G
G G G
G
Y
O R
1. When the response from the server device takes a long time
2. When the connection is dropped because there is no response from the server device
3. When the communication recovers by connection retry
* The first connection retry after the connection is
dropped is shorter than the specified interval. The
status lamp condition is an example when
connection retry is configured.
Appendix