Conrad MXD 4660 A Bedienungsanleitung Seite 9

B Measuring resistance
Important!
Make absolutely sure that all circuit components, circuits and
structural components, as well as test objects are not live.
This is how you measure resistance:
1. Connect the black measuring lead to the COM socket, and the red measuring
lead to the V/Ohm socket.
2. Press the button "OHM" in the button cluster "FUNCTION", and to set the ran-
ge, press the button corresponding to the measurement range you wish to have
in the button cluster "RANGE". Complete a continuity check for the measuring
leads by connecting the two measuring probes.
3. Next, connect the measuring probes with the object under test.
Important!
When you are measuring resistance, make sure that the measurement points
which the measuring probes touch are free of dirt, oil, soldering material or
similar. Soiled measurement points may falsify your measurement results.
For resistances greater than approx. 1 MÍ, the display may need some time to
stabilize. When "OL" is shown in the display and the bar graph shows all seg-
ments, you have exceeded the measuring range and/or the measurement path
has been interrupted.
When you measure resistance, the three displays located to right of the main
display are also active. The upper subdisplay displays the current measurement
value with a 1 s delay. The middle display shows the measurement value with a
2 s delay. The lower subdisplay shows the measurement value with a 3 s delay.
C Measuring current
This is how you measure DC or AC currents:
1. Connect the black measuring lead to the COM socket, and the red measuring
lead to the mA socket if the currents to be measured are less than 200 mA max.
(or to the 20 A socket, if the currents to be measured are in the range 200 mA to
20 A max.).
2. If measuring DC current, press the "DCA" button in the button cluster "FUNC-
TION". If measuring True RMS AC current, press the "ACA" button. Also press
the button corresponding to the measurement range you desire in the button
cluster "RANGE" (except for 200 left and 2000).
3. Connect the measuring leads to the object under test in series (as in the figure
below).
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Figure explaining how to measure curren
Fuse
~
Current-
source
Important!
Never measure currents in electric circuits which may contain vol-
tages larger than 250 VDC (or VACrms). To do so constitutes a
potentially lethal hazard. Never measure currents larger than 20 A.
Make your measurements only in circuits themselves 16 A protec-
ted, or in which output does not exceed 4000 VA.
Measurements of currents equal to 20 A may only be made for a
maximum of 30s and only at intervals of 15 minutes (cooling peri-
od for the shunt).
When you measure True RMS AC current, the middle subdisplay
shows the frequency of the AC current, while the main display
shows the current measurement value.
When you measure DC current, the three displays located to right
of the main display are also active. The upper subdisplay displays
the current measurement value with a 1 s delay. The middle dis-
play shows the measurement value with a 2 s delay. The lower
subdisplay shows the measurement value with a 3 s delay.
D Diode test and continuity check
This is how you measure diodes or semiconductor paths, or make continuity checks
on non-live wires and cables (please refer the figures shown below):
1. Connect the black measuring lead to the COM socket, and the red measuring
lead to the V/Ohm socket.
2. In the button cluster "FUNCTION", press the button " " and connect the mea-
suring probes to the object under test (which under no circumstances should
be live!).
3. In the diode test, the value displayed refers to the on-state voltage (off-state
voltage) of a Si semiconductor path (silicon p-n junction). When making conti-
nuity checks on resistances smaller than approx. 30
middle subdisplay shows "Shrt" (= short = short-circuit or conducting). There is
also a beep if the diode connected is shorted (faulty).
Ammeter/
A measuring device
Object under test,
consumer device
, there is a beep and the
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