Electrical Power Distribution Boxes EPDB

EPDB is a set of two distribution boxes inteded for twin engine small aircafts of CS23 category with 28VDC dual-channel electrical system with two batteries and two starter-generators. The main function is the reliable distribution of the electrical energy from airborne systems to airborne loads with respect to the pilot’s requests, the equipment of the aircraft and flight phases. EPDB also provides monitoring and protection of the EPS. The EPDB device is controlled by the switches from the cockpit and is implemented in the EV-55 aircraft.


  • Intelligent management of electrical energy,
  • one or two-channel concept operating possibility,
  • voltage and current measuremet,
  • light indicators of EPS state,
  • automatic functions decreasing pilot's workload,
  • power outputs short-circuit protection,
  • overcurrent protection of channels interconnection,
  • polarity reverse and overvoltage GPU protection,
  • fail-safe design with regard to AC23.1309,
  • easy maintenance and service,
  • high reliability.

Electrical parameters:

Nominal voltage: 28 V DC
Contactors: for up to 400 A
Airborne sources: - 2 starter-generators (nominally 9 kW)
- 2 batteries (typically 26 Ah)
- Ground Power Unit (nominally 12 kW)
Airborne loads: nominally 2x 7 power outputs up to 200 A


  • EASA CS-23,
  • RTCA DO-160G,
  • ČSN EN 2282:1992,
  • MIL-STD-704E,
  • FAR AC 23.1309..