Ncv Measurement - Mastech MS2225A Operation Manual

4.23 NCV measurement

1) Turn the change-over switch of the meter to the NCV
gear.
2) The top of the meter should be arranged near the
conductor. When the detected voltage is great than 110
Vac (RMS), the voltage sensing indicator may be on,
and the buzzer may make the alarm sound "beep".
Note:
1: The voltage may still exist even without instructions.
Do not determine whether there is voltage in the
conductor only by using the non-contact voltage
detectors. The detecting operation might be affected by
the socket design, insulation thickness, type and other
factors.
2: When there is input voltage to the input terminal of the
meter, the voltage sensing indicator may also be on.
3: Intrusive sources (such flashlight, motor, etc.) in the
external environment may cause a wrong trigger of
non-contact voltage detection.
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Figure 9 Schematic Diagram for Voltage Detection at NCV Gear
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