VOLTCRAFT VC-140 Bedienungsanleitung Seite 29

- The hFE measurement reacts to fluctuations in temperature. As
soon as you touch the transistor and put it into the base and
warm it up with your fingers, the measuring value may change. If
the displayed indications are unstable, remove the transistor and
wait until it has reached room temperature.
G Temperature measurement
By means of the supplied temperature adapter with NiCrNi sensor
(nickel-chrome-nickel) you can measure directly at the V/Ohm/mA
jack with reference to the COM jack temperatures that reach from -
40º C to +1000º C at the most. Take into account that "outside" the
temperature range +18° C to +28° C (= range of the guaranteed
measuring accuracy) only the thermoelement is permitted to be
exposed to the temperature that is to be measured.
Proceed as follows to measure, by means of the supplied adapter,
the temperature:
1. Set the rotary switch to "º C".
2. Connect the two 4 mm banana plug of the adapter to the
V/Ohm/mA jack and the COM jack.
3. Connect the sensor probe to an idle measuring medium (not cau-
stic liquids or solid idle bodies, heat sinks or anything similar)
Make sure that the measuring medium is absolutely
idle! Do not connect voltages. This may destroy the
device.
Disposal
Dispose of the defective, irreparable digital multimeter according to
the relevant statutory requirements.
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d) Putting-into-operation
Basic setting
Switch-on the measuring instrument by turning the rotary switch out
of the "OFF" position.
e) Assignment of the base and jacks
Transistor base (hfe)
The 4pole transistor bas has been marked symmetrically. Put the
idle transistor connectors (B) Base, (E) Emitter and C(K)ollector, as
marked, into the base jacks. The pin assignment of the different
transistors can be found in a transistor comparison book.
f) Measuring function switch = rotary switch
Ensure not to change the position of the rotary
switch during the connection of the measuring
object. Otherwise the measuring instrument may be
destroyed and your life may be in danger if the volta-
ge exceeds 25 VACrms or 35 VDC
Clockwise, the following measurements can be carried out
V = = Direct voltage (5 ranges)
V ~ = Alternating voltage (2 ranges)
hFE = Measurement of the hfe parameter of transistors
-> I- = Diode test and acoustic continuity test
ºC = Temperature measurement
A = = Direct current (4 ranges "from 2000 uA to 10A")
OHM = Resistance measurement (5 ranges)
g) Data hold "HOLD"
If you actuate the button "HOLD" situated below the display on the
left, the actual measuring value will be held. If you want to quit this
sub-function, actuate the button "HOLD" once again and a new
measurement can be carried out.
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