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play the present reading is taken 1 second later, the middle display the
reading is taken 2 seconds later and in the right display the reading
appears 3 seconds later. This means the left sub-display shows the mea-
surement value which was 1 second earlier on the main display, the
middle sub-display shows the reading which was 2 seconds earlier in the
main display and the right sub-display shows the value which was 3 seconds
earlier in the main-display.
5.9 Temperature Measurement
Temperature is displayed on the main and the sub-display.
The main display will show the temperature in Centigrade, while the
middle sub-display will show the temperature in Fahrenheit. The tempe-
rature range is from -40°C to + 1200°C. Temperature measurement is
exclusivley executed with K-type temp probes.
For temperature measurement proceed as follows:
1. Select “TEMP“ with the rotary function switch.
2. Plug in the temp probe into TEMP/CAP socket, observe the correct
polarity (narrow and wide tongue). (Use both sockets before and
after the separation bar in the middle).
Attention!
Do not connect voltages. The unit can be destroyed.
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To measure the hFE-parameter (of amplification) of a transistor follow
these steps:
1. Set the rotary function switch to hFE position.
2. Insert the transistor you want to measure into the appropriate transi-
stor socket.
Pay attention to the following points:
• observe the sequence of connection of the transistor (you will find
it in the transistor comparative table).
• Some Darlingtons or special (power) transistors contain internal
base-to-emitter resistance that could cause undependable measu-
ring results.
• The hFE-measuring value is no absolute measurement. It only indi-
cates if the transistor is operating or not. The true amplification of
a transistor depends on its operating current. This multimeter sup-
plies a base current up to 10 µA; the collector current is measured
to calculate the respective hFE-value.
• It is not possible to measure transistors which are connected in a cir-
cuit.
• It is not possible to measure the hFE-value of FETs or other unipolar
transistors.
• If a low power transistor (e.g. BD 242 etc.) has too large terminals
for the test socket, do not force it into the test socket, as it could be
damaged.
• The hFE-measurement is affected by temperature differences As
soon as you touch the transistor when you plug it in the socket and
warm it with you fingers the measuring result could be influenced.
If the hFE reading is not stable, take the transistor out and let it
come to room temperature.
Hint!
During hfe-paramenter measurement of small power transistors the
three sub-displays below the main-display are active. In the left sub-dis-
