12-8
IM 760301-01E
Item
Specifications
Effective input range
•
0 to
±
130% of the power range (see section 5.2) for DC measurement.
•
±
130% of the power range for current measurement when the voltage and current are in the
range of 1 to 130% of the measurement range. However, if the data update interval is 50 ms,
100 ms, 5 s, 10 s, or 20 s, the signal level of the synchronization source must satisfy the input
signal level of frequency measurement (see section 12.5).
*
110% for the maximum range of direct voltage and current inputs. The accuracy for 110% to
130% of the measurement range is reading error
×
1.5.
Lower limit of
Same as the lower limit of measurement frequency for voltage and current.
measurement frequency
Power factor (
λ
) influence
•
When
λ
= 0
•
5 mA to 200 mA range of a 2-A input element
•
Apparent power reading
×
0.1% in the range of 45 to 66 Hz.
•
For other frequency ranges, see below. However, the figures are reference values.
Add apparent power reading
×
(0.1 + 0.05
×
f (kHz))%
•
500 mA to 2 A range of a 2-A input element or 30-A input element
•
Apparent power reading
×
0.03% in the range of 45 to 66 Hz.
•
For other frequency ranges, see below. However, the figures are reference values.
Add apparent power reading
×
(0.03 + 0.05
×
f (kHz))%
•
When 0 <
λ
< 1
(Power reading)
×
[(power reading error %) + (power range error %)
×
(power range/apparent
power indication value) + {tan
φ
×
(influence when
λ
= 0)}] where
φ
is the phase angle between
the voltage and current.
Line filter influence
When the cut-off frequency is 500 Hz
45 Hz
≤
f
≤
66 Hz: Add 0.3% of reading. f < 45Hz: Add 1% of reading.
When the cut-off frequency is 5.5 kHz
f
≤
66 Hz: Add 0.3% of reading. 66 Hz < f
≤
500 Hz: Add 1% of reading.
When the cut-off frequency is 50 kHz
f
≤
500 Hz: Add 0.3% of reading. 500 < f
≤
5 kHz: Add 1% of reading.
Temperature coefficient
Same as the temperature coefficient for voltage and current.
One year accuracy
Add (reading error of accuracy at 6 months
×
0.5) to the accuracy at 6 months.
Accuracy when the crest
Accuracy obtained by doubling the measurement range error for the accuracy when the crest factor
factor is set to 6
is set to 3
Accuracy of Other Parameters and Computation Accuracy
•
Accuracy of apparent power S
Voltage ac current accuracy
•
Accuracy of reactive power Q
Accuracy of apparent power +
(1.0004 –
λ
2
) –
(
(1 –
λ
2
))
×
100%
of range
•
Accuracy of power factor
λ
±
[(
λ
–
λ
/1.0002) + |cos
φ
– cos{
φ
+ sin
– 1
(influence
from the power factor when
λ
= 0%/100)}|]
±
1 digit when
voltage and current is at rated input of the measurement range
•
Accuracy of phase difference
φ
±
[
|
φ
– cos
– 1
(
λ
/1.0002)
|
+ sin
– 1
{(influence from the power
factor when
λ
= 0%)/100}] deg
±
1 digit when voltage and
current is at rated input of the measurement range
•
For the accuracy of frequency fU and fI, see “Frequency Measurement” in section 12.5,
“Functions.”
•
For the accuracy of measured values WP, WP+, WP-, q, q+, and q- and the integration time, see
“Integration” in section 12.5, “Functions.”
•
For the accuracies of voltage, current, and power during harmonic measurement; the accuracies
of rotating speed and torque; and the accuracy of D/A output; see the respective sections in the
Expansion Function User’s Manual IM760301-51E
.
12.4 Accuracy