VOLTCRAFT VC190 Mode D'emploi page 43

c) LoZ AC voltage measurement
The LoZ measuring function permits alternating "AC" voltage measurements with low impedance (approx. 300 kΩ).
The lower internal resistance of the meter reduces measurement discrepancies such as phantom voltages.
The input impedance is approximately 300 kΩ and will put some strain on the circuit.
1. Set the function dial to LoZ V .
2. Connect the test leads to the terminals:
- Red test lead to the
- Black test lead to the COM terminal.
3. Connect the test lead probes to the correct test points in the circuit:
- Red: Positive polarity "+".
- Black: Negative polarity "-".
4. Read the voltage values on the display.
- The displayed value is true RMS.
- Wait for 3 minutes before next operation.
5. When finished measuring, disconnect the test leads and switch the power OFF
d) Resistance measurement (Ω)
Make sure all circuit parts, circuits, components, and other objects of measurement are disconnected from
the voltage supply and fully discharged..
1. Set the function dial to
2. Short press the SEL button 4x to select resistance measurement, "Ω" will show on the display.
3. Short press RANGE to toggle through ranges (indicated by decimal position).
4. Connect the test leads to the terminals:
- Red test lead to the
- Black test lead to the COM terminal.
5. Connect the test lead probes to the correct test points in the circuit:
- Red: Positive polarity "+".
- Black: Negative polarity "-".
Check the lines for continuity by connecting the two test leads. The impedance value should be ≤ 0.5 Ω
(inherent impedance of the measuring lines). If the value is ≥ 0.5 Ω, check the terminal connections or if
there is any damage.
6. Read the voltage values on the display.
- "OL" will appear on the display if the maximum range is exceeded or if the circuit is open.
- When measuring high resistance, it is normal to take a few seconds for readings to stabilize.
7. When finished measuring, disconnect the test leads and switch the power OFF
terminal.
.
terminal.
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