Frequency Measuring; Resistance Measuring - VOLTCRAFT VC280 Mode D'emploi

f) Frequency Measuring
The DMM can be used to measure and indicate signal voltage frequencies from 10 Hz to 10 MHz.
Proceed as follows to measure frequencies:
- Switch on the DMM and select measuring range "Hz". The display reads
"Hz".
- Plug the red measuring line into the Hz measuring jack (7) and the black
measuring line into the COM measuring jack (8) .
- Now connect the two measuring prods to the object to be measured (signal
generator, switch etc.).
- The frequency and corresponding unit are displayed.
- After measuring, remove the measuring lines from the measured object
and turn the DMM off.
g) Resistance Measuring
Make sure that all the circuit parts, switches and components and other objects of
measurement are disconnected from the voltage and discharged.
Proceed as follows to measure the resistance:
- Switch on the DMM and select measuring range "Ω ".
- Plug the red measuring line into the Ω measuring jack (7) and the black
measuring line into the COM measuring jack (8) .
- Check the measuring lines for continuity by connecting both measuring
prods with one another. The resistance value must be approximately
0 - 0.5 Ohm (inherent resistance of the measuring lines).
- For low-impedance measurements, press the button "REL" (3) to not let the
inherent resistance of the measuring lines flow into the following resistance
measuring. The display shows 0 Ohm. The automatic range selection (auto
range) is inactive. The autorange function is activated again by switching
the measuring function (e.g. press button "SELECT" 3 x).
- Now connect the measuring prods to the object to be measured. As long as the object to be
measured is not high-impedance or interrupted, the measured value will be indicated on the display.
Wait until the displayed value has stabilised. With resistances of >1 MOhm, this may take a few
seconds.
- If "OL" (overload) appears on the display, you have exceeded the measuring range or the measuring
circuit has been broken.
- After measuring, remove the measuring lines from the measured object and turn the DMM off.
If you carry out a resistance measurement, make sure that the measuring points which you
contact with the test prods are free from dirt, oil, solderable lacquer or the like. Such circum-
stances can falsify the measured result.
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