E) Impedance Measuring - VOLTCRAFT VC275TRMS Bedienungsanleitung

e) Impedance Measuring

Make sure that all circuit parts, circuits and components and other objects of measurement are
disconnected from the voltage and discharged.
Proceed as follows to measure resistance:
- Switch on the DMM and select the 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 the two measuring
prods. The impedance value must be approximately 0 - 0.5 Ohm (inherent
impedance of the measuring lines).
- For low-impedance measurements, push the button "REL" (3) to not include
the inherent impedance of the measuring lines in the following inpedance
measurement. The display shows 0 Ohm. The automatic range selection
(Auto) is deactivated. The autorange function is reactivated by pushing the
button "REL" again or by switching the measuring function (e.g. push button
"SELECT" 3 x).
- Now connect the two 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 impedances 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 is
interrupted.
- Remove the measuring lines from the object to be measured after completion of the measurement and switch off
the DMM.
If you perform a resistance measurement, make sure that the measuring points you touch with the measuring
prods are free of dirt, oil, solderable lacquer or similar. Such circumstances can falsify the measured result.
The button "REL" works only when a measured value is displayed. When "OL" is displayed, this function can-
not be activated.
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