Siemens SIMATIC PANEL PC 877 - Manual (Page 169)

Troubleshooting/FAQs
14.3 Temperature limits
SIMATIC Panel PC 877
Operating instructions, Release 07/2006, A5E00877780-01
14-3
14.3
14.3
Temperature limits
Cause
If the device is used for its intended purpose, the temperature threshold values are not
exceeded or fallen below. When the LED "Temp" on the upper left side of the operator
control unit lights up, check the following:
•
Are the fan apertures covered?
• Has the fan failed (check speed display in the SOM or on the DiagMonitor)?
• Is the ambient temperature higher than the allowed value (see "Technical data")?
• Is the total output of the power supply within the specified limit?
• Are the heatsinks inside the PC covered with dust?
Remedy
The temperature error is retained until the temperatures have fallen below the thresholds
and you have acknowledged the error alarm in the SOM program. Click on the button with
the "small broom" icon. When the error alarm has been acknowledged, the "TEMP" LED on
the devices goes off and the title bar and "SOM" icon in the status bar of the SOM program
changes from red to green. If you have not installed the SOM program or DiagMonitor, you
must restart the PC.