YOKOGAWA WT500 - Wiring for Accurate Measurements

3-12
IM 760201-01E
3.7 Wiring for Accurate Measurements
To make accurate measurements, refer to the items below when wiring the voltage input
and current input terminals.
Effects of Stray Capacitance
When measuring a single-phase device, the effects of stray capacitance on measurement
accuracy can be minimized by connecting the instrument’s current input terminal to the
side that is closest to the earth potential of the power source (SOURCE).
SOURCE
LOAD
U
I
I
U
LOAD
U
U
I
I
SOURCE
• Easily affected • Not easily affected
±
pp
p
Effects of the Measured Voltage and Current Amplitudes
SOURCE
LOAD
U
I
I
U
LOAD
SOURCE
U
I
I
U
• When the measured current is relatively
large
Connect the voltage input
terminal to the load end.
• When the measured current is relatively
small
Connect the current input
terminal to the load end.
± ±
± ±
Explanation
For details on the effects of stray capacitance and the effects of the measured voltage
and current amplitudes, see appendix 4, “How to Make Accurate Measurements.”