CorePower electronic circuit-breaker unit family

The Electronic circuit breaker units is a CorePower electronic circuit-breaker unit from Astronics with aerospace-grade grade and dual-use market. The CorePower electronic circuit-breaker unit family (ECBU, model 1448) from Astronics is a solid-state power distribution and circuit protection unit for aircraft secondary power. It replaces thermal-mechanical circuit breakers and acts as both breaker and switch for each load, so it belongs in the PMU and power management category for aircraft with 28 VDC or 115 VAC distribution.

Each channel combines the functions of a breaker, a switch and a relay in one solid-state device with no inherent wear-out mechanism. Because the unit can be installed close to the loads it serves, the wiring between source and load becomes shorter, which reduces harness weight, the number of system components and installation labour. The cockpit interface also becomes simpler, since large panels of switches and breakers are no longer needed for these loads.

The DC card takes one 28 VDC input rated for 110 A and provides 24 unidirectional 28 VDC electronic circuit breakers: 4 programmable from 7.5 to 25 A and 20 programmable from 2.0 to 10 A. The AC card takes 3-phase 115 VAC input at 60 to 800 Hz, each phase rated for 50 A, and provides 9 AC electronic circuit breakers, three per phase, which can be used singly or ganged as three-phase breakers: 3 programmable from 2 to 5 A, 3 from 2 to 10 A and 3 from 7.5 to 25 A. Protection includes a standard I2t trip, instant-trip short-circuit protection, parallel arc fault protection, secondary fuse protection and level 4 lightning protection, together with power-up and continuous built-in test.

For integration, dual RS-485 buses carry breaker control commands and report breaker status (open, closed, tripped), current and voltage. Four discrete inputs offer an alternate means of breaker control, and the control power input is dual redundant. Each card is a self-contained, individually addressable unit with customer-controlled configuration parameters. The system is expandable from 1 to 30 cards, and AC and DC cards can be mixed in the same chassis. A single-card chassis (1448-10X) and a two-card chassis (1448-20X) are offered, and the unit is convection cooled with no forced air or fan. A card measures 184 mm x 253 mm x 25.5 mm and weighs 725.7 g (DC) or 816.5 g (AC), excluding the chassis, whose enclosure is a variable.

Hardware is qualified to RTCA DO-160G and developed to RTCA DO-254 DAL B, and software is developed to RTCA DO-178C Level A. Astronics cites more than 10 million failure-free flight hours for its electronic circuit breakers.

Typical applications are secondary power distribution in business aircraft, rotorcraft, military aircraft and eVTOL platforms, where electronic load control and monitoring through the existing avionics display reduce wiring and system complexity.