YOKOGAWA WT500 User Manual page 312

Frequency Measurement
Item
What is measured
Measurement method
Measurement range
Accuracy
Display resolution
Minimum frequency
resolution
Frequency measurement
filter
Integration
Item
Modes
Measurement functions
Integration timer
Count overflow
Accuracy
Timer accuracy
IM 760201-01E
Specifications
Up to two of the voltage or current frequencies applied to an element can be selected and
measured. On models with the frequency measurement add-on option, the voltage and current
frequencies of all elements can be measured.
Reciprocal method
Data Update Interval Measurement Range
100 ms 25 Hz ≤ f ≤ 100 kHz
200 ms 12.5 Hz ≤ f ≤ 100 kHz
500 ms 5 Hz ≤ f ≤ 100 kHz
1 s 2.5 Hz ≤ f ≤ 100 kHz
2 s 1.5 Hz ≤ f ≤ 50 kHz
5 s 0.5 Hz ≤ f ≤ 20 kHz
±0.06% of reading
When the input signal level is 30% or more of the measurement range (0.5 to 440 Hz; frequency
filter on), or for external current sensor input, when it is 25 mV or more. When the input signal is
less than or equal to two times the frequency lower limit written above, and when it is greater than
or equal to 50% of the measurement range. Add 0.05% of reading when the external current sensor
input is 50 mV or less. Double the input signal level values when the crest factor is 6.
99999
0.0001 Hz
Frequency filter (see section 14.1)
Specifications
Manual, normal, continuous, real-time normal, and real-time continuous
See section 14.3 for details.
Integration can be stopped automatically by a timer that can be set to:
0000h00m00s to 10000h00m00s
When the maximum integration time (10000 hours) is reached or when an integrated value reaches
the maximum or minimum displayable integrated value,
are held and integration is stopped.
* WP: ±99999 MWh
q: ±99999 MAh
WS: ±99999 MVAh
WQ: ±99999 Mvarh
Power: ±(power accuracy + 0.02% × WS)
Current: ±(current accuracy + 0.02% of reading) if a value other than dc is selected
±(current accuracy + 0.02 × integration time (h)% of range) if dc is selected
However, there is approximately 70µs of unsampled space in each data update interval.
±0.02% of reading
14.6 Functions
*
the integration time and value at that point
1
2
3
4
5
6
7
8
9
10
11
12
13
14
App
Index
14-11