Carrying Out Measurements - VOLTCRAFT VC 120 Bedienungsanleitung

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 MOhm it may occur that the
display needs a moment to stabilise (" to adjust"). As soon as
the sign "OL" 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 sec-
ond, 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 and continuity test
Proceed as follows to measure diodes or semiconductor sections
(observe the following illustrations):
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 "-> I-".
3. The displayed value of the diode test always refers to the forward
voltage of a Si-semiconductor section (Silicon p-n junction).
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Carrying out measurements

A Direct voltage measurement
Never exceed the max. admissible input quantities.
Max. 600 VDC or VACrms with galvanic separation
from the network in the overvoltage category I or
max. 300 VDC/ ACrms in the overvoltage category II.
Do not touch any circuits or circuit elements if you
are measuring voltages that exceed 25 VACrms or
35 VDC.
Proceed as follows to measure direct voltages:
1. Connect the red instrument lead to the V/ Ohm jack and the
black instrument lead to the COM jack.
2. Set the desired voltage measuring range with the rotary switch. If
you measure direct voltages (V=), you can select among 5 mea-
suring ranges (200 mV-2000 mV-20-200-600).
3. Connect the test probes to the measuring object (load circuit,
etc.).
4. The polarity of the measuring value and the actual measuring val-
ue are indicated in the big display.
Each of the five direct voltage ranges DCV has an input resistance
of 10 MOhm.
If the sign "-" appears in front of the measuring value at the direct
voltage measurement, the measured voltage is negative (or the
instrument leads have been mixed up).
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.
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