VOLTCRAFT VC-140 Bedienungsanleitung Seite 32

Note!
Due to the fact that the measuring input is very sensitive, it may
occur with instrument leads that are not connected to any mea-
suring object that the display indicates any measuring values.
This "phenomenon" is normal and disappears as soon as you
start to carry out measurements.
C Current measurement
Proceed as follows to measure direct currents:
1. Connect the black instrument lead to the COM jack and the red
instrument lead to the mA jack if you want to measure currents of
up to 200 mA at the most or to the 10 A jack if you want to mea-
sure currents that reach from more than 200 mA to 10 A at the
most.
2. Set the rotary switch to the desired, required measuring range
(2000 uA or 20 mA or 200 mA or 10 A ).
3. Connect the instrument leads in series to the measuring object
(see the following illustration)
Fuse
Source of
– –
...
current
Do not measure currents in electric circuits in which
the voltages may exceed 35 VDC. Danger to life! Do
not measure currents that exceed 10 A. Only measu-
re in electric circuits that are protected themselves
with 10 A and in which the power cannot exceed 350 VA.
Make sure that the measurement of currents of 10 A
does not take longer than 10s at the most and take
place in intervals of 15 minutes (cooling-down phase
for the shunt).
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Ammeter /measuring
instrument
A
Measuring object/
consumer
D Resistance measurement
Make sure that all the circuit elements, circuits,
component parts and other measuring objects that
you want to measure are absolutely idle.
Proceed as follows to measure the resistance:
1. Connect the black instrument lead to the COM jack and the red
instrument lead to the V/ Ohm jack.
2. Set the rotary switch to the desired, required measuring range
(200 Ohm or 2000 Ohm or 20 kOhm or 200 kOhm or 20MOhm).
3. Now connect the test probes to the idle measuring object.
Note!
Make sure when carrying out resistance measurements that the
test points you touch with the test probes are free of dirt, oil
solderable lacquer or things like that since those substances
may falsify the measuring value.
If the resistances exceed approx. 1 M
display needs a moment to stabilise (" to adjust"). As soon as
the sign "1" appears in the display and the bar graph shows all
the segments, you have exceeded the measuring range or the
measuring section has been interrupted.
During the resistance measurement the three little displays on
the right of the main display are active. The little display at the
top indicates the actual measuring value with a delay of 1
second, the display in the centre indicates the measuring value
with a delay of 2 seconds and the little display at the bottom
indicates the measuring value with a delay of 3 seconds.
E Diode test
Proceed as follows to measure diodes or semiconductor sections or
to carry out continuity tests of idle lines and cables (observe the fol-
lowing illustrations):
Ω
it may occur that the
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