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7-16
COMPONENTS TEST PROCEDURES RESULTS
H.V.
CAPACITOR
1. Check DC 9V battery before performing
tests.
2. Select the DCV scale on the meter.
3. Using the meter, battery, and jump wire,
connect the items as illustrated in figures.
•
Terminal to terminal
•
Terminal to case
Normal:
Approximately 9V
Abnormal:
Approximately 0V
Normal:
Approximately 0V or a value
displayed in mV will be seen.
Figure 26
Figure 26
H.V. DIODE
(RECTIFIER)
STEP 1. Test the diode to see if it is shorted.
Procedure:
1. Select the ohm scale on the meter.
2. Place the meter leads across the diode as
pictured in Figure 27-1. The reading should
be “40M ohm,” “OL,” or a reading of infinity.
3. Reverse the meter leads. The reading
should again indicate a reading of infinity.
If the diode shows infinity in BOTH
directions, it is NOT shorted.
4. If the diode is not shorted, proceed to step 2.
STEP 2. Test the diode for forward biasing.
Procedure:
1. Select the DCV scale on the meter.
2. Using the meter, battery and jumper wire,
connect the items as illustrated in Figure 27-2.
This has the positive side of the battery
connected to the cathode of the diode.
3. The diode should be forward biased
therefore a voltage reading of approximately
4.7 VDC to 6.4 VDC will be read depending
on meter, battery strength, etc.
(Note: If the meter leads were reversed, a
negative voltage of the same amount would
be seen.)
Normal:
Approximately 4.7 - 6.4V