Keysight Technologies U5855A, Руководство по обслуживанию

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3 Troubleshooting and Repair
Operating and Troubleshooting Hints
20 U5855A Service Guide
Error in temperature
measurements.
The external shutter is not opened
properly. Open the external shutter fully and lock it
in place.
The surface of the IR lens is dirty or
scratched.
Clean the IR lens surface properly.
The target image is out of focus. Adjust the focus correctly.
The wrong emissivity value is set. Set the correct emissivity.
The wrong reflected temperature (RT)
value is set.
(This is not valid if emissivity is set to 1.0.)
Set the correct RT value.
Yearly calibration is not performed. Perform the calibration.
The IR sensor fails to operate properly
(sensitivity degradation). Return the U5855A to Keysight for
servicing.
Unable to save images to the SD
memory card.
The SD memory card is write-protected.
Disable write-protection of the SD memory
card.
Unable to access the SD memory
card. The SD memory card fails to operate
properly.
Check the memory status of the SD
memory card.
Replace with another compatible SD
memory card and check if it is accessible
on the U5855A.
Insert the original SD memory card to a
personal computer and check if it is
accessible.
If still fails, return the U5855A to Keysight
for servicing.
Backlight of the LCD screen does
not illuminate.
Power is not turned on.
Check the LED status indication of the
power on/off key.
A connection failure occurs between the
flexible cable (FPC) of the LCD and the
main board, or the FPC is disconnected.
Connect the U5855A to an external
monitor and check the display. If still fails,
return the U5855A to Keysight for
servicing.
Table 3-1 Troubleshooting hints (continued)
Malfunction Probable cause Troubleshooting procedure