Capacitor disconnection
78
Operating instructions RHF
ELTROPLAN
-
REVCON
Elektrotechnische Anlagen GmbH
10 Capacitor disconnection
In no load conditions (standby-operation) the frequency converter current is negli-
gible. The main current drawn at standby operation at the input of the harmonic fil-
ter is a purely capacitive reactive current which flows through the capacitor of the
harmonic filter. This reactive current component corresponds typically to ca. 20-
25% of the specified nominal harmonic filter current (depending on the respective
harmonic filter type). The power factor of the drive is at this condition very low and
changes, depending on the load, to one.
The following graphs show typical values for the true power factor of a RHF-A and
RHF-B:
Figure 32: Typical power factor of a RHF-A
Figure 33: Typical power factor of a RHF-B
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
0
20
40
60
80
100
T
ru
e
P
o
w
e
r
fac
to
r
Load [%]
True Power factor RHF-A
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
0
20
40
60
80
100
T
ru
e
P
o
w
e
r
fac
to
r
Load [%]
True Power factor RHF-B