Appendix E EN50160 Evaluation and Recording
EM720 Power Quality and Revenue Meter
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Appendix E EN50160 Evaluation and Recording
EN50160 Background
The EN50160 European standard “Voltage characteristics of
electricity supplied by public distribution systems” issued by
CENELEC defines the main physical characteristics of electric
energy supplied by low and medium voltage public
distribution systems under normal operating conditions.
The voltage characteristics are evaluated using a statistical
approach. The standard and its referenced publications
specify for each voltage characteristic:
•
Method of evaluation
•
Integrating interval for a single measurement
•
Observation period
•
Statistical indication of the probability of not exceeding
a specified limit
•
Standard compliance limits or indicative values within
which any customer can expect the voltage
characteristics to remain
Compliance Limits
For some voltage characteristics, the standard provides
definite limits that can be complied with for most of the time
considering the possibility of relatively rare excursions
beyond these limits. Limits are set with a view to compliance
for a percentage of the observation time, e.g. 95% of the
observations in any period of one week.
The following table gives the characteristics for which definite
limits have been specified by the standard.
Indicatives Values
For the remaining characteristics of the voltage, by their
unpredictable nature, the standard gives only indicative
Voltage characteristic
Compliance with stated
limits, % of time
Observation
period
Power frequency
±
1% for 95% of a week
±
1% for 99.5% of a year
+4/-6% for 100% of time
Week, year
Voltage variations (supply
voltage magnitude)
±
10% Un for 95% of time
Week
Rapid voltage changes
≤
4-5% Un (up to 10% Un) Day
Flicker (fluctuations of
voltage magnitude)
Plt
≤
1 for 95% of time
Week
Voltage unbalance
≤
2-3% for 95% of time
Week
Harmonic voltage
THD
≤
8 for 95% of time
Week
Interharmonic voltage
To be defined
Week
Mains signaling voltage
Within “Meister-curve” for
99% of time
Day
