Frequency Measurement - Conrad Electronic VC-227 Manuel D'instructions

During resistance test, make shure that the measuring points, which
you touch with test-lead tips are free of dirt, oil or solder varnish etc.
This might influence the measuring value and also capacitors which
are still carrying voltage.
For resistors over 2 MOhm the display needs a few seconds to
stabilize. As soon as "OFL" is displayed and an acoustic signal is
emitted you exceeded the measuring range or the leads are open.
5.3 Continuity Check and Diode Test
a) Continuity Check " ":
Attention!
Never measure capacitors which carry voltage, as a possible
discharge could disturb your measuring unit.
With this function you can check dead leads, fuses, circuits etc. with
an audible signal.
Proceed as follows:
1. Switch on your measuring unit:
2. Set the rotary function switch to (9) "
is automatically set in the mode continuity check. Additionally the
respective symbol is shown on top of the display.
3. Afterwards connect the test probes with the object to be measured.
If the resistance is less than 100 Ohm a beep sound is emitted.
b) Diode Test
Attention!
For diode tests pay attention, that the diode and the circuit in
which it is probably built in, do not carry voltage. All capacities
must be discharged.
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/ ". The multimeter
Proceed as follows:
1. Switch on your multimeter
2. Set the rotary function switch (9) to "
3. Press the key " " (= manual range selection) once; the symbol
for acoustic continuity check disappears from the display.
4. Now connect the test-lead points with the object under measure-
ment, a dead semiconductor line, the red test-lead points to the
anode, the black test-lead points to the cathode (as a rule it is
marked with a coloured ring, point etc.).
If you check a diode line in forward direction, you will measure a
voltage of approx. 0.25 V (Germanium) or 0.7 V (Silicon), if the diode
line is not defective.
If you now exchange the test-lead points, this means red to the
cathode and black to the anode, you check the so called reverse
direction. If "OFL" is displayed the diode is o.k. If however a value
between 0 V and approx. 3.5 V is displayed, you connected the object
under measurement wrong or it is defective.

5.4 Frequency measurement

Attention!
Observe the maximum input limits! Do not connect the unit to
voltages exceeding 250 VDC max. or 250 VAC (rms=eff). It is life
dangerous to touch the terminals or probe tips when measuring
voltages over 25 VAC or 35 VDC.
Disconnect the test leads from the test points before changing
the meter function and range. The sensitive electronic of the
measuring unit might be destroyed and this can be dangerous
to you.
Proceed as follows:
1. Select "Hz" with the rotary function switch.
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