Siemens S7 - page 106

Configuring Communication Connections
106 SIMATIC NET NCM S7 for Industrial Ethernet
C79000-G8976-C129–06
Attributes AccessDescription
Inactivity Time The inactivity time specifies the interval after which
the connection is terminated if no sign of life is
received from the partner (6–180 s, default 30 s).
Modifiable
Window Time The window time specifies the interval at which sign
of life frames are sent. For SIMATIC NET CPs, the
window time is set to 1/3 of the inactivity time (2–60
s, default 10 s). Sign of life frames are sent to check
the connection when there is no data traffic.
Display only
Notice
Window Time and Inactivity Time
The partner responds to a sign of life frame with a frame. They are therefore sent
to the partner at the intervals of the window time. To avoid unwanted connection
termination, the inactivity time should be at least three times as long as the
window time.