Capacitor Specs

Capacitor life is mainly affected by voltage and temperature (see charts 1 and 2). Aerovox capacitors for HID Lighting
applications are typically marked “90°C” or “100°C max”. They are designed for 60,000 hours continuous duty at rated
voltage and average operating temperatures of 90°C. Ongoing Accelerated Life Test programs verify Aerovox capacitor
designs and production units. Special designs may be supplied where capacitors operate continuously above 90°C.
Temperature is defined as the highest reading on any area of capacitor case. Operation over 90°C (212°F) will reduce
operating life. Guideline: each 6.5 degree rise over 90°C reduces life by 50%. Aerovox capacitors can be operated at low
temperatures (to -40°C without derating). Aerovox capacitors are non-polar (terminals/electrodes can be reversed), unlike
many “electrolytic” capacitors which have plus and minus terminals that will cause catastrophic failure when reversed.
Along with being non-polar, metallized film capacitors are self-clearing. During momentary faults, small areas of metallized
electrodes vaporize and capacitor function is restored (usually with small reductions in micro farads until end of capacitor
life).

Aerovox capacitors include: agency listings outlined below), accelerated life testing programs, and protective devices
(interrupters). Ongoing testing programs total over 500 million component test hours each year at Aerovox New Bedford.
Safety Agency listings are continuously monitored programs.Testing also includes fault-current requirements on
interrupter mechanisms per UL#810. Protective devices cause open circuits at end of capacitor life, versus short circuits
that can be caused by capacitors without protective devices.

Construction

General:

Aerovox capacitors outlined in this catalog utilize two basic types of construction; oil-filled metal cases and dry units
(epoxy filled plastic cases). These capacitor designs, materials, and construction are all documented per ISO 9001 and
closely controlled. Materials used in Aerovox capacitors are only obtained from certified sources and monitored. Aerovox
capacitors cover a wide range of case styles including dual-caps (two capacitors in one case).

Dielectrics:

Aerovox capacitors use special types of polypropylene film. Polypropylene films are the most energy efficient dielectric
materials commercially available for continuous duty AC voltage applications. Capacitor efficiency is measured as % DF
(dissipation factor). Aerovox capacitor DF’s are typically less than 0.1% at 60Hz and 70°C (158F). Other types of
capacitors typically have much higher DF’s. Examples; Aluminum Electrolytic capacitors can have DF’s over 10% at 25°C
and polyester film DF increases with temperature. Aerovox capacitors are capable of continuous duty with very low Mfd
losses (see chart 3).

Polypropylene plastic films used by Aerovox are specially made to close tolerance thicknesses that are engineered for
various AC voltage ratings at 50/60 HZ RMS. These films are metallized, and wound into rolls (two layers with opposing
margins). Roll ends are then sprayed with metal to connect layers and form capacitor electrodes at each end. Note: oil-
filled capacitors can use thinner dielectrics than comparable dry capacitors.

Aerovox capacitors include: agency listings outlined below), accelerated life testing programs, and protective devices
(interrupters). Ongoing testing programs total over 500 million component test hours each year at Aerovox New Bedford.
Safety Agency listings are continuously monitored programs.Testing also includes fault-current requirements on
interrupter mechanisms per UL#810. Protective devices cause open circuits at end of capacitor life, versus short circuits
that can be caused by capacitors without protective devices.

Aerovox metal case capacitors use soybean-oil or Polyisobutylene-oil, to extend design life. These oils protect metalized
film from corrosion, aid heat transfer, and help suppress corona (which may otherwise cause premature failures). Aerovox
oil-filling processes utilize proprietary cycles of vacuum and heat to remove ambient moisture in cases (which would
otherwise reduce operating life of capacitors). Protective devices (interrupters) in oil-filled metal cases: Connections to
film rolls are made with tabs welded to each end and connected to case terminals through an interrupter mechanism. As
illustrated in Drawing A, interrupter mechanisms cause an open circuit at end of capacitor life.

Dry Plastic Case Capacitors

made by Aerovox for HID lighting applications up to 400 VAC and can be supplied with wire leads or terminals. For similar
performance, dry capacitors must use thicker dielectrics than oil-filled capacitors. Therefore, case sizes of dry capacitors
are typically larger than oil-filled styles with similar design life performance. Plastic case dry capacitors are lighter weight
than oil-filled units, and provide better corrosion resistance than metal case parts. Costs vary considerably depending on
styles and quantities being compared. In general, plastic case parts with terminals offer lowest costs in higher quantities.
However, oil-filled units may offer lower costs and quickest delivery for small quantities of off-the-shelf standard products.

Unprotected Dry Plastic Case Capacitors

made by Aerovox are outlined on Page 12 of this brochure. They can be supplied with insulated wire leads or terminals.
Wire lead styles use suffix “-P” on capacitor part numbers. Wire leads are 8" long 18 gauge stranded copper wire with UL
listed insulation rated for 150C. Terminal styles use suffix “-PQ” and have standard single blade 1/4" quick-disconnects
(like used on oil-filled capacitors). As clearly noted in this brochure, unprotected capacitors may fail short.

Connections:

While oil-filled parts are only supplied with terminals, plastic case styles are made by Aerovox with terminals or wire leads.
Wire leads are 8" long 18 gauge stranded copper wire with UL listed insulation rated for 150°C. Terminals are 1/4" wide x
1/32" thick standard electrical terminals that mate to connectors available from a variety of sources. Standard terminals
are two-blade style on oil-filled metal cases (with ground lugs and three or four blade terminals available on special
request). Standard terminals on Aerovox plastic cases are 1/4" single blades (two-blade available on special request).

Marking:

Each capacitor label includes the following information: AEROVOX, four-digit date code (yr/wk), µF (micro farads), VAC
rating, our part numbers, and safety agency symbols. Special marking is also available. PROTECTED is clearly marked
where that feature is included, otherwise NOT PROTECTED is shown on labels where plastic cases are unprotected. (See
pages 5 to 7.) Dual-Section capacitors have Micro farads printed next to the terminal (common in middle).

Temperature Markings:

Plastic case parts are labeled 100°C max. Standard oil-filled oval cases made by Aerovox which had been labeled 90°C
can now also be labeled 100°C max (because these oil-filled capacitors perform as well on accelerated tests as plastic
case capacitors labeled 100°C max).