UNI-T UT256A Operating Manual page 9

UT256A User Manual
Caution:
Do not input voltages higher than DC 60V or AC 30V to
avoid personal injury.
Before measuring the resistance online, switch off the power
supply of the circuit, and fully discharge all capacitors to
ensure accurate measurement.
If the resistance is >0.5Ω when the test leads are short-
circuited, please check the test leads for looseness or other
abnormalities.
If the measured resistor is open or the resistance exceeds
the maximum range, the LCD will display "OL".
Measurement result = displayed value – resistance of
shorted test leads
5. Non-contact Voltage (NCV) Sensing (Picture 7)
1) Turn the function switch to the NCV position, and use the
SELECT button to switch to high voltage measurement
("EFHI") or low voltage measurement ("EFLo"). When the
voltage is >48V, select "EFHI"; when the voltage is <48V,
select "EFLo".
2) Bring the NCV sensor close to the charged AC wire under
test. As the intensity of the detected voltage increases, the
more the segments ("—", "— —", "— — —" or "— — — —")
are displayed, the more frequently the buzzer beeps and
the indicator flashes. When the voltage is sensed in EFLo
mode, the indicator blinks in green, and when the voltage
is sensed in EFHI mode, the indicator blinks in yellow until
it turns red.
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UT256A User Manual
Picture 7
Caution:
If the distance between the NCV sensor and AC wire is
different, the intensity sensed will vary.
Frequency of the detected voltage: 50Hz~60Hz
NCV sensing is not used as a basis for touch. Use the test
leads for contact measurement to determine whether the
voltage is safe before touch to prevent electric shock.
6. Others
1) Auto power off: During measurement, if there is no operation
of the function switch or any button for 15 minutes, the
meter will automatically shut down to save power. Users
can wake it up by pressing any button or restart it after
turning the function switch to the OFF position.
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