VOLTCRAFT VC950 - Impedance Measurement; Diode Test

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d) Impedance measurement
Make sure that all circuit parts, circuits and compo-
nents and other objects of measurement are dis-
connected from the voltage and discharged.
Proceed as follows to measure impedance:
- 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 the two
measuring prods. The impedance value must be approximately
0 - 1.5 Ohm (inherent impedance of the measuring lines).
- 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.
- Alwaysremovethemeasuringlinesfromtheobjecttobemeas-
ured after completion of the measurement and switch off the
DMM.
If you carry out an impedance measurement, make sure that the measuring points you touch with the measuring
prodsarefreefromdirt,oil,solderablelacquerorsimilar.Suchcircumstancescanfalsifythemeasuredresult.
e) Diode test
Make sure that all circuit parts, circuits and com-
ponents and other objects of measurement are
disconnected from the voltage and discharged.
- Switch on the DMM and select the measuring range
.
Press the button to switch measurement func-
tions. The diode symbol appears in the display. Pressing this
button again takes you to the first measuring function, etc.
- Plug the red measuring line into the Ωmeasuringjack(7)
and the black measuring line into the COM measuring
jack(8).
- When the measurement input/measurement circuit is open
and short-circuited (e.g., if the diode is defective), “- - - - -”
will be displayed.
- Connectthetwomeasuringprodswiththeobjecttobemeas-
ured (diode).
- LCD shows “OL” when the Diode is tested in Reverse Direc-
tion, please revise Diode and retest. If LCD still shows “OL”,
the Diode is defective.
- Always removethe measuring lines fromthe object tobe
measured after completion of the measurement and switch
off the DMM.