YOKOGAWA WT500 - Page 310

14-9
IM 760201-01E
Specifications
3
2
1
4
5
6
7
8
9
10
11
12
13
14
App
Index
Item Specifications
Line filter influence When the cutoff frequency is 500 Hz
45 to 66 Hz: Add 0.3% of reading. Less than 45 Hz: Add 1% of reading.
When the cutoff frequency is 5.5 kHz
66 Hz or less: Add 0.4% of reading. 66 to 500 Hz: Add 1.2% of reading.
Temperature coefficient Same as the temperature coefficients for the voltage and current.
One year accuracy Reading error of accuracy at 6 months × 1.5.
Accuracy when the crest
factor is set to 6
Same as the accuracy when the crest factor is 3 after doubling the measurement range.
Other Computation and Measurement Accuracies
• Accuracy of apparent power S Voltage accuracy + current accuracy
• Accuracy of reactive power Q
Accuracy of apparent power + (
(1.0004 – L
2
)
–
(1 – L
2
)
) ×
100% of range
• Accuracy of power factor
λ
±[(
λ
–
λ
/1.0002) + |cos
f
– cos{
f
+ sin – 1(influence from the
power factor when
λ
= 0%/100)}|] ± 1 digit
when voltage and current are at the measurement range rated
input.
•
Accuracy of phase difference
f
±[|
f
– cos – 1(
λ
/1.0002)| + sin – 1{(influence from the power
factor when
λ
= 0%)/100}] deg ± 1 digit
when voltage and current are at the measurement range rated
input.
•
For the accuracies of frequencies fU and fI, see “Frequency Measurement” in section 14.6,
“Functions.”
•
For the accuracies of integrated values WP, WP+, WP–, q, q+, and q– and the integration time
(Time), see “Integration” in section 14.6, “Functions.”
•
For the accuracies of voltage, current, and power during harmonic measurement, see “Harmonic
Measurement” in section 14.6, “Functions.”
14.5 Accuracy