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Plasma Display Panel Troubleshooting - 2007
Troubleshooting Steps
Define, Localize, Isolate and Correct
•
Define
Look at the symptom carefully and determine what circuits could be
causing the failure. Use your senses Sight, Smell, Touch and Hearing. Look for
burned parts and check for possible overheated components. Capacitors will
sometimes leak dielectric material and give off a distinct odor. Frequency of power
supplies will change with the load, or listen for relay closing etc.
•
Localize
After carefully checking the symptom and determining the circuits to
be checked and after giving a thorough examination using your senses the first check
should always be the DC Supply Voltages to those circuits under test. Always confirm
the supplies are not only the proper level but be sure they are noise free. If the
supplies are missing check the resistance for possible short circuits.
•
Isolate
To further isolate the failure check for the proper waveforms with the
Oscilloscope to make a final determination of the failure. Look for correct Amplitude
and Timing of the signals also check for the proper Duty Cycle of the signals.
Sometimes “glitches” or “road bumps” will be an indication of an imminent failure.
•
Correct
The final step is to correct the problem. Be careful of ESD and make
sure to check the DC Supplies for proper levels. Make all necessary adjustments
and lastly always perform a Safety AC Leakage Test before returning the product
back to the Customer.
Troubleshooting