SATEC PM175 Manual - Manual (Page 99)

‎Chapter 4 PAS Application Software EN50160 Evaluation and Recording
Series PM175 Powermeters 99
it becomes greater than the end threshold on all affected
phases including a threshold hysteresis.
The basic voltage dip measurement is one-cycle RMS voltage
updated each half-cycle.
The voltage dip threshold can be changed in the meter via the
EN50160 PQ Recorder setup.
Statistical Results
The PM175 provides the statistical evaluation of voltage dips
using the classification established by UNIPEDE. Dips are
classified by residual voltage magnitude and duration as
shown in Appendix E.
Indicative Values
Under normal operating conditions the expected number of
voltage dips in a year may be from up to a few tens to up to
one thousand. The majority of voltage dips have a duration
less than 1 s and a depth less than 60%.
Voltage Interruptions
Voltage interruptions correspond to temporary loss of supply
voltage on all phases lasting less than or equal to 3 minutes in
the event of short interruptions, and more than 3 minutes for
long interruptions.
Method of Evaluation
The voltage interruption is detected when the voltages on all
phases fall below the interruption threshold (as per IEC 61000-
4-30) specified by the EN50160 at a level of 1%Un. The
interruption threshold can be changed in the meter via the
EN50160 PQ Recorder setup.
The basic voltage measurement is one-cycle RMS voltage
updated each half-cycle.
Statistical Survey
The PM175 provides the statistical evaluation of voltage
interruptions using the classification recommended by
Eurelectric’s Measurement guide for voltage characteristics.
Interruptions are classified by duration as shown in Appendix
E.
Indicative Values
Under normal operating conditions the expected number of
short voltage interruptions in a year may be from up to a few
tens to up to several hundreds. Short interruptions generally
last less than a few seconds.
The annual frequency of long interruptions may be less than
10 or up to 50 depending on the area.
Temporary Overvoltages
Temporary overvoltages are sudden rises of the voltage RMS
value of more than 110% of nominal voltage. Temporary
overvoltages may last between 10 milliseconds and one
minute.
Method of Evaluation
A temporary overvoltage is classified as one polyphase event
regardless of the shape and of the number of phases affected
(as per IEC 61000-4-30). An event can begin on one phase