App-29
IM 760301-01E
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App
App
Index
Appendix
Measurement period
Data update interval
Data update interval
Measurement period
Synchronization
source setting: OFF
Unintended zero crossing caused by pulse noise
• Setting the Synchronization Period When Measuring a Three-Phase Device
If a three-phase device is measured with input elements 1 and 2 using three-phase,
three-wire system, set the synchronization source of input elements 1 and 2 to the
same signal. For example, set the synchronization source of input element 1 and 2 to
U1 (or I1, the same synchronization source). In effect, the measurement periods of
input elements 1 and 2 match, and the
Σ
voltage,
Σ
current, and
Σ
power of the three-
phase device can be measured with high accuracy.
Likewise, if a three-phase device is measured with input elements 1, 2, and 3 using
three-phase, four-wire system, set the synchronization source of input elements 1, 2,
and 3 to the same signal.
To facilitate this sort of configuration, the synchronization source setting on the
WT3000 is linked to the
Σ
wiring unit of the wiring system (when the independent
setting of input elements is OFF). If the independent setting of input elements (see
section 4.2) is turned ON, the synchronization source of each input element in the
Σ
wiring unit can be set independently.
Measurement period
Data update interval
Synchronization source
Input signal U1
Input signal U2
Input signal U3
U1 (or I1)
Input element 1
Input element 2
Input element 3
Synchronization source setup example
Appendix 6 Setting the Measurement Period