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VT30 V2.1 10/06
4
Operation
Always test the meter on a known live circuit before taking measurements
Voltage Measurement
1.
Note: The voltage tester will turn on automatically when voltages
higher than 4.5V AC/DC are detected.
2.
Touch the positive (L2) and negative (L1) test leads to the device or
circuit under test.
3.
If the voltage is higher than 4.5V AC/DC, the LCD will light and
display the reading. The stepped voltage bargraph scale in the
display will also indicate the reading.
4.
For AC voltages, the LED will light and the “AC” icon will appear in
the display. For DC voltages, the “DC” icon will be displayed. If the
DC voltage is negative, a minus sign will be displayed before the
digital readout.
Single Lead AC Voltage Detection
To check for the presence of voltage (between 100V and 480V)
using only the positive test lead (L2), touch the lead to the device or
circuit under test. If voltage is present, the LED will light.
Note
: In this mode, the actual voltage is not displayed; only the
presence of voltage is detected.
Low Impedance Voltage Measurement
Due to the lowered internal impedance, capacitive voltage is
suppressed so that the reading shows the actual voltage
applied. This can be used to quickly identify phantom voltages.
1.
Hold the two test tips on the measuring points to be
tested.
2.
Press the two low impedance test buttons
simultaneously.
3.
The Low Impedance LED will light and the applied
voltage will be displayed on the LCD.
Note
: The maximum duty cycle in this mode is 5 seconds for
voltages up to 250V and 3 seconds for voltages up to
690V. Allow 10 minutes between each reading.
Note
: Measuring from hot to ground may trip any GFCI equipped circuits.