YOKOGAWA WT500, Руководство пользователя

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14-10
IM 760201-01E
14.6 Functions
Measurement Functions and Measurement Conditions
Item Specifications
Frequency range DC, or 0.5 Hz to 100 kHz
Crest factor Can be set to 3 or 6 (when the rated input of a given measurement range is applied).
300 for the minimum effective input.
Measurement period Period used to determine and compute measurement functions.
• Except for ampere hours (q) during DC mode and watt hours (WP), the measurement period is
set using the zero crossing points of the reference signal (synchronization source).
• In harmonic display (optional):
The measurement period is the first 1024 points from the beginning of the data update interval
at the harmonic sampling frequency.
Wiring system Can be set to one of the following five types:
(1) 1P2W, single-phase, two-wire; (2) 1P3W, single-phase, three-wire; (3) 3P3W, three-phase,
three-wire; (4) 3P4W, three-phase, four-wire; and (5) 3P3W (3V3A), three-phase, three-wire
with three-voltage, three-current method.
The selectable wiring systems vary depending on the number of input elements that are installed.
Measurement range See section 14.1.
Scaling Set the current sensor transformation ratio, VT ratio, CT ratio, and power factor in the range
of 0.0001 to 99999.9999 when applying the external current sensor, VT, or CT output to the
instrument.
Input filter A line or frequency filter can be set. See section 14.1 for details.
Averaging • For measurement functions used in normal measurement
The following kinds of averaging can be performed on voltage U (Urms, Umn, Udc, Urmn, and
Uac), current I (Irms, Imn, Idc, Irmn, Iac), power P, apparent power S, and reactive power Q
functions. Power factor
λ
and phase difference angle
f
are determined from the averaged P
and S values.
Exponential averages or moving averages can be determined.
• Exponential average
The attenuation constant can be set to 2, 4, 8, 16, 32, or 64.
• Moving Average
The average count can be set to 8, 16, 32, or 64.
• For measurement functions used in harmonic measurement
• Exponential average
The attenuation constant can be set to 2, 4, 8, 16, 32, and 64.
Data update interval The update interval can be set to 100 ms, 200 ms, 500 ms, 1 s, 2 s, or 5 s.
Response time The maximum response time is the data update interval × 2. However, this is only when displaying
numeric values.
Hold The hold feature holds the display.
Single measurement The single measurement feature executes a single measurement while the display is held. During
integration, the display is updated with the most recent data.
Zero-level compensation
(NULL)
Compensation range: ± 10% of range (when the crest factor is set to 3)