Aerospace Circuit Breaker handles currents up to 50 A.

Press Release Summary:

Weighing 60 g, single-pole Model 4140 is intended for 115 V or 28 Vdc applications from 20-50 A. Temperature-compensated unit offers operating temperature of -67 to 257°F and provides consistent trip curve characteristics from -67 to 194°F. In addition to aircraft applications, breaker is suitable for ground vehicles where resistance to mechanical vibration and shock are required. It also meets Mil-Std 202, method 101 test condition B, for salt spray test.

Original Press Release:

E-T-A's 4140 Aerospace Circuit Breaker Handles Currents to 50A in a Small Package

E-T-A's 4140 High Performance Circuit Breaker has ratings to 50A and is significantly smaller than similar models

Chicago, July 28, 2004 - E-T-A Circuit Breakers announced the 4140, a temperature-compensated circuit breaker with current ratings up to 50A in a package that is smaller than mil spec MS 24571 and 10 percent lighter than most competing devices. With this addition to E-T-A's high performance circuit breaker line, design engineers can select a high-performance E-T-A circuit breaker for any rating from 1 to 50A.

Up to 10 Percent Less Weight
The 4140 circuit breaker, which is the single-pole companion to the company's 5140 three-pole high performance model, provides
higher current carrying capacity with minimum weight. Even a modest weight reduction is beneficial in aerospace designs, because hundreds of circuit breakers may be used in a single aircraft. No comparable breaker weighs less than the 4140.
Even with optional auxiliary contacts, it weighs only 60 grams - 10 percent less than most competing devices.

Compact Package
The 4140 thermal circuit breaker was designed for 115 V (400 Hz) or 28 VDC applications from 20 to 50 amps, an exceptionally high current rating for a circuit breaker in a compact form factor. This is accomplished by a design that allows for heat dissipation and careful selection of materials used in the bimetal and contacts.

In addition to aircraft applications, the 4140 circuit breaker is suitable for use in rugged ground vehicles where high performance circuit protection and resistance to mechanical vibration and shock are required.

The 4140 breaker meets Mil-Std 202, method 101 test condition B, for salt spray test, making it suitable for marine applications, where corrosion, mechanical specifications, and weight are prime concerns.

The 4140 Series makes an excellent candidate for military use under the COTS (commercial off-the-shelf) program.

E-T-A's new 4140 circuit breaker is temperature-compensated, providing consistent trip curve characteristics from -55 to +90°C (-67 to 194°F). Operating temperature limits are -55 to 125°C (-67 to 257°F). Typical life is 5000 mechanical cycles and 2500 inductive cycles, assuring long, reliable service. Maximum altitude is 15,000 m (49,175 ft).

For applications where signaling is required (such as indicating to a pilot light that a circuit breaker has tripped), auxiliary contacts are available as an option. The polarized or unpolarized auxiliary contacts are
rated for 0.5 A at 28 VDC. Other options include thread neck size selection and terminal hardware. Accessories include an actuator extension, identification collars and lock out rings.

Price and Availability
E-T-A's 4140 Series circuit breaker is available now. Priced around $130.00 in medium quantilies (100-500).

The 4140 circuit breaker is the newest member of E-T-A's broad family of high performance circuit breakers. Lower current ratings are available through the 4120 and 483 Series. A three pole version of the 4140 is available in the 5140 Series. For more information call E-T-A at 847-827-2700, or visit

About E-T-A
E-T-A Circuit Breakers is the leading manufacturer of circuit breakers for equipment and is the only resource for all circuit protection technologies: thermal, thermal-magnetic, magnetic and high performance. E-T-A circuit breakers are available in more than 150 models and 350,000 different configurations. E-T-A is also a world leading manufacturer of control and monitoring products, and solid state remote power controllers (SSRPCs). With the North American headquarters in Chicago, the company serves industrial OEMs and end-users.

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