YOKOGAWA CW120 - Chapter 8. Instantaneous Value Measurement; Measuring Instantaneous Values

8-1
IM CW120-E
Instantaneous Value Measurement
8
Chapter 8. Instantaneous Value Measurement
8.1 Measuring Instantaneous Values
The CW120/121 power meters have two modes for measurement:
1. Instantaneous value measurement: Measures the rms voltages and
rms current of individual phases, and power, reactive power, power factor,
and frequency.
2. Electric energy measurement: In addition to the values in the
instantaneous value measurement mode, measures the electric energy.
Measurement is performed continuously and integration is started and
stopped by using the
keys.
This section describes instantaneous value measurement.
● Displayed Data
The display format changes over between the above
automatically depending on the elapsed time.
Item
Rms voltage
Rms current
Active power
Reactive power
Power factor
Frequency
Electric energy (watt-hours)
Elapsed time of integration
Unit
V
A
W
Var
—
Hz
Wh
Hour: minute:second
Hour: minute
Hour
Displayed Name
V1, V2, V3
(differs depending on the wiring method).
A1, A2, A3
(differs depending on the wiring method).
W
Var
PF
Hz (input frequency of V1)
Wh
00:00:00TIME
0000:00TIME
00000hTIME
● Measurement Procedure
1. Perform safety checks
with reference to Chapter 3, “Precautions for Safe Measurement.”
2. Turn on the power to CW120/121
with reference to Chapter 4, “Connecting Power Supply and Turning
Power On/Off.”
3. Perform wiring
with reference to Chapter 5, “Wiring.”
4. Set the ranges and wiring method
with reference to Chapter 6, “Setting Ranges and Wiring Method.”
5. Set measurement conditions
with reference to Chapter 7, “Making Settings.”
6. Measure instantaneous values.