Wire Connection Modes - UNI-T UT513B User Manual

Note:
Do not measure AC power supply over 750Vac or DC power supply over
1000Vdc. It is possible to display higher voltage (10%), but it may damage the
tester.
Avoid electric shock when working with high voltage.
After completing all measurement operations, please disconnect the test
lead with the measured circuit, and remove the test lead from the input
terminal.
9.3.3 Capacitance Measurement
As a part of insulation measurement, the tester has circuit capacitance measurement
function. Without high voltage output, press capacitance measurement button,
the default range is 500V. Under capacitance measurement function, there are
only three rated voltage ranges including 250V , 500V and 1000V, press
to switch the ranges. For capacitance measurement, the tester calculate the
circuit capacitance by measuring the charge and voltage of circuit.
Capacitor
Black
Red
Fig. 9.3.3.1 Wire connection of capacitance measurement
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UT513B/C User Manual
and
UT513B/C User Manual
C=
Calculation formula:
Where C is measured capacitance, Q is the accumulated charge in the measured
object and U is the voltage of both ends of measured object.
Note: If the withstand voltage of the capacitor is less than the output voltage of
the capacitor, please do not perform measurement to avoid capacitor damage.
When measuring capacitor with polarity, please note that red test lead is the
negative of power output and black is positive, to avoid breaking down the
capacitor with polarity.
X. Wire Connection Modes
10.1 . Cable Insulation Resistance Testing
A. Insulation resistance measurement with two-wire connection
There is leakage current at the surface of inner insulation layer near the end of
cable, the leakage current is included in the measured current of "-" terminal,
causing the measured resistance to be lower than actual insulation resistance.
This mode can be used for non-ultrahigh resistance measurement, as shown in
the figure below:
Shield
Black
Red
Fig. 10.1.1 Two-wire connection
Q
U
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