Current Measurement (Magnitude Of Supply Current); Frequency Measurement - METREL Energy Master MI 2883 Instruction Manual

MI 2883 Energy Master
Line voltage:
Phase voltage crest factor:
Line voltage crest factor:
The instrument has internally 3 voltage measurement ranges, which are automatically
selected regarding to the nominal voltage.

5.1.3 Current measurement (magnitude of supply current)

Standard compliance: Class A (Section 5.13)
All current measurements represent RMS values of the samples of current magnitude
over a 10/12-cycle time interval. Each 10/12-cycle interval is contiguous and non-
overlapping.
Current values are measured according to the following equation:
Phase current:
Phase current crest factor:
The instrument has internally two current ranges: 10% and 100% range of nominal
transducer current. Additionally Smart current clamps models offer few measuring
ranges and automatic detection.

5.1.4 Frequency measurement

Standard compliance: IEC 61000-4-30 Class A (Section 5.1)
During RECORDING with aggregation time Interval: ≥10 sec frequency reading is
obtained every 10 s. The fundamental frequency output is the ratio of the number of
integral cycles counted during the 10 s time clock interval, divided by the cumulative
duration of the integer cycles. Harmonics and interharmonics are attenuated with digital
filter in order to minimize the effects of multiple zero crossings.
The measurement time intervals are non-overlapping. Individual cycles that overlap the
10 s time clock are discarded. Each 10 s interval begin on an absolute 10 s time clock,
with uncertainty as specified in section 6.2.19.
For RECORDING with aggregation time Interval: <10 sec and on-line measurements,
frequency reading is obtained from 10/12 cycles frequency. The frequency is ratio of
10/12 cycles, divided by the duration of the integer cycles.
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