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2.1. If the diode is faultless, the screen will display “Vf” and “Vr”
values. The screen color will be green.
2.2. If the "Vf” value is higher than normal, the screen color will be
yellow.
2.3. If the diode is faulty, the screen color will be red.
The operability of the rectifier should be decided on the basis of the “Vf” readings and type
(model) of the diode (stabilitron). The “Vf” absolute value is not always a key parameter when
checking the rectifier. It is important to pay attention to the spread between the “Vf” values of
different diodes of the same rectifier. For example, for a rectifier that can carry 50 A, “Vf” = 0.850
V is quite typical. The rectifier can be considered faultless If the spread between “Vf” values of
the diodes doesn’t exceed ± 0.020 V. For the 120A rectifier, "Vf" = 0.850V is already a critical value.
The diode with such a "Vf" value shall be considered faulty.
2.4. In case of a short or open circuit failure, the screen color will be red and either the “SHORT
CIRCUIT’ or ‘DIODE BREAKDOWN’ message will be displayed correspondingly.
User Manual - MS021 Tester
English
