Datasheet

18 GMC-I Messtechnik GmbH
Ð With adjustment potentiometer, adjust to full scale deflection .
Ð Connect the measurement cables as shown.
Ð Read the resistance value on the
 scale giving consideration to the
multiplication factor.
Attention!
!
Only electrically dead items may be measured. External volt-
ages would falsify the measured result.
After the range switch has been switched from one resistance measur-
ing range to another, always check the full scale deflection
and
correct with potentiometer, if required.
4.7 Test of Diodes and Transistors
The resistance measuring ranges k x 1 and k x 10 are also suited
for coarse functional tests of diodes and transistors. A short circuit or
an interruption of a diode and/or a diode path between base, collector
and emitter of a transistor can be found in a simply way with a "resis-
tance measurement". The polarity of a diode and the base connection
of a transistor can also be found in this way. The device under test
cannot be destroyed as the measuring voltage is 1 V at a maximum
and the measuring current. 2.2 μA or 22 μA at a maximum. From this
limitation of the measuring voltage and the measuring current it fol-
lows, however, that semi-conductors with relatively high reverse and/
or residual current, such as power diodes and power transistors, for
instance, and also rectifiers with several series-connected elements
cannot be tested as, due to the small measuring current, the difference
between the readings in forward and/or reverse direction are not
sufficiently marked.
Ð Set the range switch to position k
 x 1 or k x 10.
Ð Set switch to position „ON“.
Ð With adjustment potentiometer adjust to full scale deflection
.
Ð Connect the measuring leads to the sockets „A|“ and „“.
Ð Connect diode or transistor according to the following table and
measure both in forward and reverse direction.