Power Quality Logger
Using the 1745 Power Quality Logger
35
Flicker
Flicker is the visual impression of unsteadiness in a light source whose
luminance or spectral distribution changes over time. Flicker, see Figure 14, is
logged in accordance with the IEC 61000-4-15 standard. The short-term (st)
flicker P
st
is logged over a default standard interval of 10 minutes, and is used
to calculate the long-term (lt) flicker P
lt
by taking the sliding average of 12
short term values. The interval value can be changed as needed in PQ Log.
Formula for Plt Function
3
12
1
3
12
∑
=
=
i
Pst
Plt
Time
Flicker [%]
Interval length => 1 Pst
12 x interval length => 1 flicker value Plt
egb020.eps
Figure 14. Measuring Flicker Values
Содержание 1745
Страница 12: ...1745 Users Manual iv ...
Страница 14: ...1745 Users Manual vi ...
Страница 72: ...1745 Users Manual 58 ...