Operating instructions

Functions
11.5 Fan monitoring
SIMATIC Panel PC 677B
96 Operating Instructions, 05/2007, A5E01035609-01
WD monitoring times (TWD)
The monitoring times can be set in increments of one second within a range from 3 to 255
seconds.
Note
The watchdog is retriggered if the monitoring time is changed at the active watchdog (that is
while the watchdog is running)!
11.5 Fan monitoring
The function monitors operation of the enclosure and power supply fans. When a fan fails,
the following reactions are triggered:
Response Option
SOM or DiagMonitor software is activated None
The temperature error is retained until the cause of the fan failure has been rectified and the
error is reset in one of the following ways:
● Acknowledgement of the error message by means of the SOM program
● Restart of the device