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Troubleshooting
4-3
Power-on self test
During the power-on sequence, the Model 2500 will perform a checksum test on its
EPROM and test its RAM. If one of these tests fails, the instrument will lock up.
Front panel tests
There are three front panel tests: one to test the functionality of the front panel keys and
two to test the display. In the event of a test failure, refer to “Display board checks” for
details on troubleshooting the display board.
KEYS test
The KEYS test lets you check the functionality of each front panel key. Perform the fol-
lowing steps to run the KEYS test.
1.
Display the MAIN MENU by pressing the MENU key.
2.
Using the EDIT keys, select TEST, and press ENTER to display the SELF-TEST
MENU.
3.
Select DISPLAY-TESTS, and press ENTER to display the following menu:
FRONT PANEL TESTS
KEYS DISPLAY-PATTERNS CHAR-SET
4.
Select KEYS, and press ENTER to start the test. When a key is pressed, the label
name for that key will be displayed to indicate that it is functioning properly. When
the key is released, the message NO KEYS PRESSED is displayed.
5.
Pressing EXIT tests the EXIT key. However, the second consecutive press of EXIT
aborts the test and returns the instrument to the SELF-TEST MENU. Continue
pressing EXIT to back out of the menu structure.
DISPLAY PATTERNS test
The display test lets you verify that each pixel and annunciator in the vacuum fluorescent
display is working properly. Perform the following steps to run the display test:
1.
Display the MAIN MENU by pressing the MENU key.
2.
Select TEST, and press ENTER to display the SELF-TEST MENU.
3.
Select DISPLAY-TESTS, and press ENTER to display the following menu:
FRONT PANEL TESTS
KEYS DISPLAY-PATTERNS CHAR-SET
Summary of Contents for 2500
Page 2: ...Contains Calibrating and Servicing Information Model 2500 Dual Photodiode Meter Service Manual...
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Page 13: ......
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Page 16: ...1 PerformanceVerification...
Page 28: ...2 Calibration...
Page 56: ...3 RoutineMaintenance...
Page 59: ...3 4 Routine Maintenance Model 2500 Service Manual...
Page 60: ...4 Troubleshooting...
Page 74: ...5 Disassembly...
Page 81: ...5 8 Disassembly Model 2500 Service Manual...
Page 82: ...6 ReplaceableParts...
Page 93: ...6 12 Replaceable Parts Model 2500 Service Manual...
Page 94: ...A Specifications...
Page 98: ...B CalibrationReference...
Page 108: ...C CalibrationProgram...
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Page 121: ...Keithley Instruments Inc 28775 Aurora Road Cleveland Ohio 44139 Printed in the U S A...