Installation guide

74 Estimating Network Performance
890 USE 100 00
3.8 Getting and Clearing Statistics
3.8.1 Local Device Statistics
When you issue commands to Get Local Statistics or Clear Local
Statistics, the action is handled by the local device’s peer processor. No
transaction occurs on the Modbus Plus network. The operation is
completed by the end of the MSTR function execution in the local
device. Figure 32 illustrates a Get Local Statistics operation in
controller A.
CONTROLLER
PEER
PROCESSOR
MODBUS PLUS NETWORK
NOT USED IN TRANSACTION
REQUESTRESPONSE
Figure 32 Sample GET LOCAL ST ATISTICS
3.8.2 Remote Device Statistics
When you issue commands to Get Remote Statistics or Clear Remote
Statistics, the action is handled by the destination device’s peer
processor. Timing of the transaction is affected by the network token
rotation time and the scan time of the originating device. The scan
time of the destination device is not a factor.
CONTROLLER
A
PEER
PROCESSOR
CONTROLLER
B
PEER
PROCESSOR
MODBUS PLUS NETWORK
REQUEST >
< RESPONSE
Figure 33 Sample GET REMOTE ST ATISTICS