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Chapter 4 Detailed functions description
4.1 Basic Measurements
The AFM-8A series meter can measure voltage, current, power, frequency, power factor,
demand, etc.
4.1.1 Demand
This meter consists of several types of demand calculation: total active power demand,
total reactive power demand, total apparent power demand, phase A current demand,
phase B current demand, and phase C current demand. When demand is reset, demand
memory registers are set as 0.
Demand calculating mode can be set as sliding block and
fi
x block according to user.
4.1.1.1 Sliding block
When using the sliding block interval method, user selects an interval from 1 to 60
minutes, which is the period of the calculation. The demand updates every 1 minute as the
block slides once. The following
fi
gure description takes a 15-minute block interval as an
example:
4.1.1.2 Fix block
Like the sliding block, a calculation period is set first, and the increment is also one
minute. However, only one demand is calculated in the whole period, that is the demand
update interval is the calculation cycle time. The following figure description takes a
15-minute block interval as an example: