Troubleshooting/FAQs 14.3 Temperature limits

14.3Temperature 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.

SIMATIC Panel PC 877

14-3

Operating instructions, Release 07/2006, A5E00877780-01

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Siemens PANEL PC 877 operating instructions Temperature limits, Cause, Remedy