Film capacitors – Capacitors for Power Factor Correction
WindCap capacitors
B25668A6836A375
MKK690-D-12.5-11
Resonance cases
Resonance cases must be avoided by appropriate application design in any case. Maximum total
RMS capacitor current (incl. fundamental harmonic current) specified in technical data must not be
exceeded.
Re-switching vs. phase-opposition
In case of voltage interruption, a sufficient discharge time has to be ensured to avoid phase-
opposition and resulting high inrush currents.
Vibration resistance
The resistance to vibration of capacitors corresponds to IEC 68, part 2–6.
Max. test conditions:
Test duration
6 h*
Frequency range 1
Displacement amplitude
10 ... 55 Hz*
0.75 mm*
*corresponding to max. 98.1 m/s” or 10 g
These figures apply to the capacitor alone. Because the fixing and the terminals may influence the
vibration properties, it is necessary to check stability when a capacitor is built in and exposed to
vibration. Irrespective of this, you are advised not to locate capacitors where vibration amplitude
reaches the maximum in strongly vibrating equipment.
Mechanical protection
The capacitor has to be installed in a way that mechanical damages and dents in the aluminum can
are avoided.
Grounding
The threaded bottom stud of the capacitor has to be used for grounding. In case grounding is done
via metal chassis that the capacitor is mounted to, the layer of varnish beneath the washer and nut
should be removed. The maximum tightening torque is 10 Nm.
FK PFC R&D
July 2007
Page 6 of 8
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