Rigol DM3068, Руководство по обслуживанию

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RIGOL Chapter 5 Troubleshooting & Maintenance
Service Guide for DM3068
5-8
meter starts testing the screen and a message “Press ·Help· Key to Switch,
Hold ·Help· Key to Exit” is shown on the screen.

If you press Help, the screen switches between Full white (all pixels go on)
and Full black (all pixels go out). Observe the luminance fluctuation of the
LCD and inspect if there is any light spot or dark spot.

If you press and hold Help for about 2 seconds, the display returns to
normal measurement state.
If the brightness of LCD is out of control, enter the normal working state and
regulate the brightness and contrast under Utility to further confirm the fault
cause. IF the brightness cannot be adjusted, there may be something wrong
about the mainboard. If LCD does not shine, LCD or mainboard may have been
damaged.
If bright point or scotoma occurs, the LCD module may be damaged.
Before replacing the parts, please try to pull out the connecting line between
LCD and mainboard and reconnect and test to get rid of connectivity failure.
4. Keypad
The DM3068 provides a self-check program to inspect whether the button and
backlight from the panel are normal.
Inspection method:
Press and hold the first menu key on the left side and turn on the multimeter,
after about 5 seconds and until you hear a sound, the meter starts testing the
keypad. The basic measurement keys, parameter keys and trigger control keys
are flashing during the test and a status picture is shown on the screen. When
you first press a button, the corresponding icon from the picture changes to
reverse video and then varies with the button you have pressed.
If no movement happens after you pressed a button, this button or related
circuit may have a fault.
If the backlight of some or all buttons does not flash while you execute the
self-check, a fault or mistake may occur in that or all backlights or related
circuit(s).
Try to pull out the connecting cable between LCD and mainboard and reconnect
them to test the connectivity to get rid of connectivity failure before replacing a
part.
Replace the keypad and/or rubber button if the problem is proved.
NOTE:
Restoring to factory default may be useful for some problems, for example:
To preclude the possibility of setup error and indeterminate fault:
Press Utility

System

Setup

Factory and restart the meter.