YOKOGAWA WT310E, Руководство пользователя

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1-12 IM WT310E-01EN
Moving Average
The specified average count is used to compute linear averages according to the equation below.
D
n
=
M
n − (m − 1)
+ • • • M
n − 2
+M
n − 1
+M
n
m
D
n
: Displayed value of the linear average of m items of numeric data from the n–(m–1)
th
to the n
th
time
M
n–(m–1)
: Numeric data at the n–(m–1)
th
time
………………………………………………
………………………………………………
M
n–2
: Numeric data at the n–2
th
time
M
n-1
: Numeric data at the n–1
th
time
M
n
: Numeric data at the n
th
time
m: Average count (select from 8, 16, 32, and 64)
Measurement Functions That Are Averaged
The measurement functions that are directly averaged are indicated below. Other functions that use
these functions in their computation are also affected by averaging. For details about how the values
of measurement functions are determined, see appendix 1 in the Getting Started Guide, IM WT310E-
02EN.
Measurement Functions Used in Normal Measurement
• U, I, P, S, and Q
• λ, Φ, Cf U, and Cf I are computed using the averaged values of Urms, Irms, P, S, and Q.
Measurement Functions Used in Harmonic Measurement (Option)
• U(k), I(k), and P(k)
• λ(k) and Φ(k) are computed using the averaged values of P(k) and Q(k).
• Uthd, Ithd, Uhdf(k), Ihdf(k), and Phdf(k) are computed using the averaged values of U(k), I(k),
and P(k).
k: The harmonic order
Q(k): reactive power of harmonic order k
Measurement Functions That Are Not Averaged
The following measurement functions are not averaged.
Measurement Functions Used in Normal Measurement
fU, fI, U+pk, U–pk, I+pk, I–pk, P+pk, P−pk, Time, WP, WP+, WP–, q, q+, and q–
Measurement Functions Used in Harmonic Measurement (Option)
ΦU(k), ΦI(k), and fPLL
1.2 Measurement Conditions