Datasheet

© KEMET Electronics Corporation • P.O. Box 5928 • Greenville, SC 29606 • 864-963-6300 • www.kemet.com F3114_C4AQ • 2/6/2018 9
Power and AC Film Capacitors – Printed Circuit Board Mount Power Film Capacitors
C4AQ, Radial, 2 or 4 Leads, 500 - 1,500 VDC, for DC Link (Automotive Grade)
Dissipation Factor
Dissipation factor is a complex function involved with the ineciency of the capacitor. The tgδ may change up and down
with increased temperature. For more information, please refer to Performance Characteristics.
Sealing
Hermetically Sealed Capacitors
When the temperature increases, the pressure inside the capacitor increases. If the internal pressure is high enough, it can
cause a breach in the capacitor which can result in leakage, impregnation, lling uid or moisture susceptibility.
Resin Encased/Wrap & Fill Capacitors
The resin seals on resin encased and wrap and ll capacitors will withstand short-term exposure to high humidity
environments without degradation. Resins and plastic tapes will form a pseudo-impervious barrier to humidity and
chemicals. These case materials are somewhat porous and through osmosis can cause contaminants to enter the capacitor.
The second area of contaminated absorption is the lead-wire/resin interface. Since resins cannot bond 100% to tinned wires,
there can be a path formed up to the lead wire into the capacitor section. Aqueous cleaning of circuit boards can aggravate
this condition.
Barometric Pressure
The altitude at which hermetically sealed capacitors are operated controls the voltage rating of the capacitor. As the
barometric pressure decreases, the susceptibility to terminal arc-over increases. Non-hermetic capacitors can be affected
by internal stresses due to pressure changes. This can be in the form of capacitance changes or dielectric arc-over as well
as low insulation resistance. Heat transfer can also be affected by altitude operation. Heat generated in operation cannot be
dissipated properly and can result in high RI2 losses and eventual failure.
Radiation
Radiation capabilities of capacitors must be taken into consideration. Electrical degradation in the form of dielectric
embitterment can take place causing shorts or opens.