YOKOGAWA WT1800 User Manual page 39

2.5 Precautions When Wiring the Circuit under Measurement
Use measurement cables with dielectric strengths and current capacities that are appropriate
for the voltage or current being measured.
Example: When making measurements on a current of 20 A, use copper wires that have a
conductive cross-sectional area of 4 mm
The act of connecting measuring cables may cause radio interference, in which case users
will be required to correct the interference.
Note
• If you are measuring large currents or voltages or currents that contain high frequency components, take
special care in dealing with mutual interference and noise when you wire the cables.
• Keep measurement cables as short as possible to minimize the loss between the circuit under
measurement and the instrument.
• The thick lines on the wiring diagrams shown in sections 2.9 to 2.11 are the parts where the current flows.
Use wires that are suitable for the current levels.
• To make accurate measurements of the voltage of the circuit under measurement, connect the
measurement cable that is connected to the voltage input terminal to the circuit as closely as possible.
• To make accurate measurements, separate the measurement cables as far away from the ground wires
and the instrument's case as possible to minimize static capacitance to the ground.
• To measure the apparent power and power factor more accurately on an unbalanced three-phase circuit,
we recommend that you use a three-voltage, three-current method with a three-phase, three-wire system
(3P3W; 3V3A).
2-10
CAUTION
2
or greater.
IM WT1801-03EN