PEC Miniverter, Руководство пользователя

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6.1 Method of Checking Diodes Using an Ohmmeter
In this method you use an ohmmeter comparable to a Triplett Model 310 meter and proceed as
follows:
1. Disconnect the power input to the converter.
2. Set the ohmmeter at x times 10.
3. Read the forward and reverse resistance of the diode by placing one test prong on the heat sink
or diode stud and the other on the pigtail, then reverse the prongs to read reverse resistance.
4. From readings obtained, the following conclusions can be drawn.
a. A good diode will have a resistance reading, but it will be other than those listed below
under items (b) and (c).
a. If the resistance reading is infinite in both directions, the diode is open and, therefore,
no good.
b. If the resistance reading is zero in both directions, the diode is short circuited and also
no good.
The resistance reading value of a good diode may vary from one diode to another. This variance
gives no indication as to the quality of the diode. These reading are only taken to indicate if a diode
is short circuited or open.
6.2 Method of Checking Diodes Using a Continuity Tester
IMPORTANT: Before testing any diodes, check the continuity tester by touch-
ing the probe and clip together. If it is functioning properly, the light will go on.
1. Disconnect one end of the diode.
2. Apply clip end of the continuity
tester to the diode pigtail and the
probe end to the diode stud. See
Figure 8 .
3. Apply probe end of the continuity
tester to the diode pigtail and the
clip end to the diode stud. See
Figure 8 .
If the light in the continuity tester
goes on in both steps 2 and 3, this
indicates a shorted diode condition.
If the light in the continuity tester
does not go on in steps 2 and 3, this
indicates an open diode condition.
A good diode will cause the light in the continuity tester to go on in one direction only.
Figure 8 Continuity Tester Attached to Diode