YOKOGAWA WT500 User Manual page 36

Input Filter (See section 4.8 for operating instructions)
Data Update Rate (See section 4.9 for operating instructions)
IM 760201-01E
There are two types of input filters. The WT500 makes measurements by synchronizing
to the input signal. Therefore, the frequency of the input signal must be measured
accurately.
Line Filter
The line filter is inserted into the voltage, current, and power measurement input
circuits and directly affects the voltage, current, and power measurements (see the
block diagram in section 2.1). When the line filter is turned on, the measured value
does not contain high frequency components. The voltage, current, and power of
inverter waveforms, strain waveforms, etc., can be measured with their high frequency
components eliminated. You can select the cutoff frequency.
Frequency Filter
The frequency filter is inserted into the frequency measurement input circuit and affects
frequency measurements. It affects the detection of the measurement period for voltage,
current, and power measurements (see section 4.7 and appendix 5). The frequency filter
is also used to accurately detect the zero crossing (see section 2.2 and appendix 5). The
frequency filter is not inserted into the voltage, current, and power measurement input
circuit. Therefore, the measured values include high frequency components even when
the frequency filter is turned on.
Note
The frequency filter is turned on when the line filter is set to 500 Hz.
You can select an update interval from 100 ms, 200 ms, 500 ms, 1 s, 2 s, and 5 s.
The numeric data is updated at the selected interval. To capture relatively fast load
fluctuations in the power system, select a fast data update rate. To capture relatively low
frequency signals, select a slow data update rate.
2.3 Measurement Conditions
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App
Index