Measurement Operation Instruction; Ac Voltage Measurement; Dc Voltage Measurement - UNI-T UT15B PRO User Manual

9. Measurement Operation Instruction

Check the built-in AA 1.5Vx2 batteries, the symbol will be displayed if the battery is low and needs to be
replaced in time, which. With the symbol of displaying, please notice that the measuring voltage or current
shall not exceed the specified value in order to ensure safety!
9.1 AC Voltage Measurement (See Figure 3)
1) Turn the function selection knob to the AC voltage scale.
2) Insert the red test lead to V port and the black one to the
COM port, and connect the tips of two test leads to both
ends of measuring voltage separately (with the load in
parallel) to measure.
3) When the input impedance of the meter is about 10MΩ,
the load may cause measurement error in circuit with high
impedance. In most cases, if the circuit impedance is under
10kΩ, error can be ignored (0.1% or lower).
4) Press SELECT button in ACV mode to enter the VFC
low-pass filter mode, then the high frequency interference
signal will be filtered out through internal specific filter circuit
to ensure the accuracy. It can be applied in VFC frequency
conversion voltage.
5) The AC measurement value is true RMS value.
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UT15B PRO/UT17B PRO User Manual
True RMS
V
VFC
CAT III 1000V
CATIV 600V
Figure 3
UT15B PRO/UT17B PRO User Manual
9.2 DC Voltage Measurement (See Figure 4)
1) Turn the function selection knob to the DC voltage scale.
2) Insert the red test lead to V port and the black one to the
COM port, and connect the tips of two test leads to both
ends of measuring voltage separately (with the load in
parallel) to measure.
3) The input resistance of DC voltage is infinity (≥3GΩ).
No attenuation when measuring weak signal with high
precision. Some digits will show in open circuit, which is
normal without measurement affecting.
Note:
It is forbidden to input voltage higher than 1000Vrms.
Damage may occur though it is possible to measure higher
voltage.
Use caution to avoid electric shock when working with high
voltages.
Before each use, verify tester operation by measuring a
known voltage.
True RMS
CAT III 1000V
CATIV 600V
Figure 4
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