WAGO 750-872/020-000 Manual page 91

Network Loading
More Information
It is not possible to define hard key data, because of the reasons above.
So please take as support for your planning the Application Notes, published in
the InterNet, with appropriate projects showing the efficiency of the Web
visualization.
Please find Application Notes under www.wago.com.
WAGO-I/O-SYSTEM 750
ETHERNET TCP/IP
Fieldbus Controller 750-872/020-000
low-priority process.
Make sure when configuring tasks that there is sufficient
processor time available for all processes. The
"freewheeling" task call option is not suitable in conjunction
with the "WebVisu", as in this case the high-priority PLC
program suppresses the web server. Instead of this, use the
"cyclic" task call option with a realistic value.
The PLC browser provides an overview of the real
execution times of all CoDeSys tasks with the command
"tsk".
If operating system functions for the handling of "sockets"
or the "file system" are used in a PLC program for example,
these execution times are not taken into account by the "tsk"
command.
The Ethernet controller 750-872/020-000 has just one CPU,
which is responsible both for running the PLC program and
for handling the network traffic.
Ethernet communication demands that every telegram
received is processed, regardless of whether it is intended
for the 750-872/020-000 or not.
A significant reduction in network loading can be achieved
by using "switches" instead of "hubs".
However, broadcast telegrams can only be suppressed by
the sender or by means of configurable switches, which
feature broadcast limiting.
A network monitor such as www.ethereal.com will give an
overview of your current network loading.
Attention
Please pay attention that the bandwidth
limit, which can be configured in the Web
Based Management System under the
„Ethernet" link. It is not a suitable means
for increasing the operating reliability of
the "WebVisu", as in this case telegrams
are ignored or rejected.
Fieldbus Controller • 83