Type CQ72 MIL Spec Capacitors

TYPE CQ72 CAPACITORS offer superior electrical characteristics, couple with small size and are designed to meet or exceed the requirements of MIL-C-19978/3E.

TYPE CQ72 CAPACITORS are designed for a wide range of uses including filter, bypass, and coupling applications in the low audio frequency range, energy storage, laser discharge, power factor correction, etc. The CQ72 style case and nternal construction permit operation in any position. Glazed ceramic bushings or silicone rubber rivet terminals are used, and, in the voltage ranges of 2 KVDC and greater, ceramic is the insulation in the terminal assembly.

type-cq72-capacitorCase: Metal with terminals
Temperature: -55 or -65 °C to +85 or +125°C
Capacitance: 0.1 uF to 15 uF
Capacitance Tolerance: ±10% std. ±5%, ±2% and ±1% on request.
Voltage: 400 V to 12.5 KV

• Energy Storage                   • Rectifier Filters
• Power Factor Correction  • Tuned Filters
• Spark Suppression              • Pulse Discharge
• HV Test Equipment            • Integrating Circuit

SIZE: The CQ72 case sizes listed next page are not necessarily the smallest possible for a given capacitor. If size and shape are more critical to your application than MIL Spec certification, Chicago Condenser Corporation can work with you to optimize a capacitor to your needs. Wide range of can sizes in several styles is available.

IMPREGNANT: CQ72 capacitors are premium products impregnated with a synthetic dielectric fluid which is appreciably more costly than high grade mineral oil. The use of other impregnants in commercial versions of CQ72 designs can result in cost reductions, at the expense of operating temperature range, flammability, and MIL Spec certification. Should your application allow the use of a less costly impregnant, Chicago Condenser Corporation will be pleased to quote on such a design.

CONTAINER: CQ72 capacitors are built to the rigid specifications of MIL-C-19978/3E. The case size is dictated by the specification. For some capacitors in the CQ72 line, the windings would fit in a much smaller case. Chicago Condenser Corporation’s CMP product line extends the quality and conservative design of CQ72 capacitors to the commercial realm and higher voltages. As a result of the greater freedom in optimizing CMP designs to the customer’s application, these capacitors are generally much more cost effective for non-MIL Spec applications. While CMP capacitors can be fabricated to any voltage level, above 50 KV, Chicago Condenser Corporation’s BAM capacitors tend to be much more cost effective. These capacitors are fabricated in an insulating tubular container with a terminal at each end. The case, therefore, becomes the insulation between the terminals. For further details, see Chicago Condenser Corporation’s CMP and BAM pages.

WINDING DESIGN: Capacitors can be constructed in a range of winding designs (e.g., extended foil, tab constructions, etc.) and can be fabricated from a wide range of dielectric materials including polypropylene, polyester (“Mylar”), polycarbonate, etc. with varying layers and configurations of paper. Each combination of construction and materials has its advantages and disadvantages. CQ72 capacitors must be made of paper and polyester (Mylar) impregnated with a synthetic dielectric fluid. Polyester has the advantages of relatively high dielectric constant, high dielectric strength, and wide operating temperature range. It does have a number of disadvantages, including relatively high dielectric absorption, poor high frequency characteristics, and a large variation of dielectric constant and dissipation factor with temperature. This makes CQ72 polyester film capacitors suitable for DC and audio frequency applications for which the high dielectric absorption and variation of dissipation factor and the capacitance with temperature are not critical.

TOLERANCE ±10% standard
±5%, ±2%, ±1% are also available
IMPREGNATION Impregnated and filled with synthetic oil, and hermetically sealed
CASE and FINISH Terneplate or hot-tinned steel
Coat of grey synthetic enamel
TERMINALS Characteristic “B”: hermetic silicone rubber sealed rivet terminals
Characteristic “D” or “E”: metalized ceramic terminals
Terminals meet L5 requirements of MIL-I-10 specifications
DIELECTRIC Polyester resin film and the finest grade Kraft paper impregnated with synthetic oil
BRACKETS Footed or spade bolt type can be furnished
MOUNTING POSITION All CQ72 capacitors will operate satisfactorily mounted in any position
TEST VOLTAGE Terminal-to-Terminal: 200% rated voltage for 1 minute at room temperature
Terminal-to-Case: 200% rated voltage + 1 KV for 1 minute at room temperature
Test voltage shall be applied and discharged through a resistance of at least 1 Ω/rated voltage to a maximum of 5 KΩ
FLASHOVER ≤ 5 KV: ceramic terminals will withstand 125% rated voltage at a pressure of 12 KPa, (1.7 psia or 0.12 bar), equivalent to 50,000 feet altitude
≥ 6 KV: terminals will withstand 125% rated voltage at a pressure of 68 KPa (10 psia), equivalent to 10,000 feet altitude
OPERATING TEMPERATURE -55 or 65 °C to +85 or +125°C depending on case size

Proceed next page for standard ratings, dimensions and terminal configurations.