To Next Page

To Previous Page

App-18

IM WT310E-01EN

As another example, if an inverter is being measured and the current waveform distortion is smaller

than the voltage waveform distortion, set the synchronization source to the current signal.

Voltage

waveform

Current

waveform

Synchronization source

set to the current signal

Zero Crossing

• Therising(orfalling)zerocrossingisthetimewhenthesynchronizationsourcepassesthrough

level zero (the center of the amplitude) on a rising (or falling) slope. The measurement period on

this instrument is between the first rising (or falling) zero crossing and the last rising (or falling) zero

crossing in the data update interval.

• Thisinstrumentdeterminesthemeasurementperiodonthebasisofthefirstrisingorfallingzero

crossing within the data update interval.

Data update interval

Measurement period

Synchronization

source

● Rising zero crossing

○ Falling zero crossing

When the Period of the Synchronization Source Cannot Be

Detected

If the total number of rising and falling zero crossings on the input signal that has been set as the

synchronization source is less than two within the data update interval, the period cannot be detected.

Also, the period cannot be detected if the AC amplitude is small. For information on the detectable

frequency levels, see the conditions listed under “Accuracy” under “Frequency Measurement” in

section 7.4, “Features,” in the Getting Started Guide, IM WT310E-02EN.

If the synchronization is set to voltage and this instrument cannot detect the voltage period, it will

detect and use the current period. If this instrument cannot detect the current period either, the entire

data update interval is used to average the sampled data.

Likewise, if the synchronization is set to current and this instrument cannot detect the current period,

it will detect and use the voltage period. If this instrument cannot detect the voltage period either, the

measurement interval is the entire data update interval.

Data update interval

Measurement period

Appendix 4 Setting the Measurement Period

YOKOGAWA WT310EH User Manual

Questions and Answers: