YOKOGAWA WT500 User Manual page 346

Appendix 5 Setting the Measurement Period
App-26
Data update interval
Measurement period
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 a 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 elements 1 and 2 to U1. The
measurement periods of input elements 1 and 2 will match, and the
and power of a three-phase device can be measured more accurately.
Σ
Likewise, if a three-phase device is measured with input elements 1, 2, and 3 using a
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 WT500
is linked to the wiring unit of the wiring system (when independent input element
Σ
configuration is off). If independent input element configuration (see section 4.2 for
details) is turned on, the synchronization source of each input element in the
can be set independently.
Data update interval
Measurement period
Synchronization
source
Input signal U1
Input signal U2
Input signal U3
Synchronization Source Setup Example
Input element 1
Input element 2
Input element 3
When the
synchronization
source setting is
turned off
U1 (or I1)
Data update interval
Measurement period
voltage, current,
Σ Σ
wiring unit
Σ
IM 760201-01E