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4.3 Harmonics and Power Quality Analysis
4.3.1 Harmonics
AFM-8A series meter can measure and analyze THD, 2nd to 63rd individual harmonics.
4.3.2 Phase angle
Phase angle indicates the angle between phase 1 or phase 1-2 voltage and other
voltage/current parameters. Angle ranges from 0 to 360 degrees. This function is to help
users
fi
nd out the relationship between all input signals avoiding wrong wiring. When it is
set to “3P3W”, it gives out the phase angles of V23, V31, I1, I2, I3 corresponding to V12.
For other settings, it gives out the phase angles of V2, V3, I1, I2, I3 corresponding to V1.
4.3.3 Unbalance analysis
AFM-8A series meter analyzes the AC sampling values to obtain the values of voltage
and current unbalance.
4.4 Event logging function
AFM-8A series meter has the function of event logging. That is, when a parameter
changes so that the defined event triggering condition is established and the duration
exceeds the preset time limit, the event record will be started. The parameter number and
value of the event, the status of the event and the time stamp of the event are recorded,
as events and up to 16 such records can be stored in the memory. In addition to the
condition setting from event log, the alarm output of the relay and the DO alarm output of
the extended DIO modules are also the source of the event log.
Before using the event logging function to complete the conditions set, logging enabled,
any incomplete or incorrect settings will result in the failure of the record. The setting
operation is completed by setting the corresponding register. It should be specially
explained that the settings of these registers must be set by means of communication.
4.4.1 Setting of single event logging function
Table 4-1 indicates the
fi
rst log of settings, there are 16 logs in total with the same format.
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Table 4-1