184
Specications of Input, Output, and Measurement
(4) Frequency measurement specications
Number of
measurement
channels
Up to 8 channels (fU1 to fU8, fI1 to fI8), depending on the number of installed modules
Measurement
method
Reciprocal method
The waveforms processed with the zero-cross lter are measured.
Measurable range 0.1 Hz to 2 MHz (The display shows 0.00000 Hz or – – – – – – Hz if measurement was not
possible.)
The range is limited by the input module’s measurement band and the measurement lower
frequency limit setting.
Measurement
accuracy
±
0.005 Hz
Assuming all the following conditions are met:
• Measurement parameter: voltage frequency
• Data refresh interval: 50 ms or more
• Voltage range: 15 V range or higher
• Inputted waveform: a sine wave with a magnitude of at least 50% of the range
• Frequency range: 45 Hz to 66 Hz
Under conditions other than listed above:
±
0.05% of reading
(With a sine wave at least 30% of the measurement range of the measurement source)
Display resolution 0.10000 Hz to 9.99999 Hz, 9.9000 Hz to 99.9999 Hz,
99.000 Hz to 999.999 Hz, 0.99000 kHz to 9.99999 kHz,
9.9000 kHz to 99.9999 kHz, 99.000 kHz to 999.999 kHz,
0.99000 MHz to 2.00000 MHz
(5) Integration measurement specications
Measurement mode Can be chosen between RMS and DC for each wiring.
(The DC mode is selectable for the 1P2W wiring conguration only.)
Measurement item Current integration (Ih+, Ih−, Ih), Active power integration (WP+, WP−, WP)
The instrument measures Ih+ and Ih− only in DC mode; Ih only in RMS mode.
Measurement
method
Digital calculation based on current and active power. (Calculations are performed using
not-averaged values during averaging.)
In DC mode: Integrates current values and instantaneous power values for each polarity at
every sampling point.
In RMS mode: Integrates current RMS values and active power values at the
measurement intervals.
Only the active power is integrated by polarity. (Active power is integrated by polarity at
every period of the synchronization source.)
(The sum of integrated eective power values of a polyphase wiring conguration is the
sum of eective power values by polarity at the measurement intervals.)
Measurement
interval
Same as the data refresh interval
Display resolution 999999 (6 digits + decimal point),
Starts from the resolution assuming 1% of each range to be 100% of range.
Measurable range 0 to
±
99.9999 PAh
0 to
±
99.9999 PWh
Integration time 0 s to 9999 h 59 min. 59 s
Integration stops if the integration time exceeds the range.
Integration time
accuracy
±
0.02% of reading (−10
°
C to 40
°
C)
Integration accuracy
±
(Current or active power)
±
(Integration time accuracy)
Backup function None
If a power outage occurs during integration, the integration stops after power is restored
and the integration data is reset.