Environmental Control Unit / Prime Power Unit (ECU/PPU)

Features

Multi-function unit – Provides cooling, heating, make-up air, and 28-vDC electrical power to the Avenger turret
High-efficiency power generation – 6.0 kW @ 28 vDC output with <100 mV RMS ripple, independent of engine speed or load
Rugged diesel power plant – Hatz 2G-40 air-cooled diesel engine with brushless permanent magnet generator and variable-speed governor
Advanced environmental control – 12,500 Btu/hr cooling (R-134a refrigerant, desert-ready) and 10,000 Btu/hr electric heating
NBC protection – 40 CFM airflow through a 0.3-micron Nuclear, Biological, Chemical filtration system
Lightweight and portable – Total system weight under 440 lb including 5.5 gallons of fuel for up to 8 hours of operation
Reliable electronics – Solid-state control components mounted on printed circuit boards for enhanced durability

The MLS Environmental Control Unit / Prime Power Unit (ECU/PPU) is engineered to meet the requirements of the U.S. Army Aviation and Missile Command (AMCOM) Avenger Air Defense System Specification MIS-46246D, using state-of-the-art components for maximum reliability and performance.

The ECU/PPU provides cooling, heating, make-up air, and 28-vDC electrical power directly to the Avenger turret. Its power plant is a Hatz 2G-40 air-cooled diesel engine coupled with a shaft-mounted, three-phase, brushless permanent magnet generator. Output and engine speed are regulated by a variable-speed governor, which automatically optimizes performance depending on system load.

The vapor cycle air conditioning system uses environmentally compliant R-134a refrigerant and is designed to operate in extreme desert conditions. Heating is supplied through high-efficiency electric heaters, while make-up air passes through a Nuclear, Biological, Chemical (NBC) filtration system, providing 40 CFM at 0.3-micron filtration.

Despite its rugged capabilities, the complete ECU/PPU system weighs under 440 pounds, including fuel for eight hours of continuous operation. It delivers 12,500 Btu/hr cooling capacity and 6.0 kW at 28-vDC output, with voltage ripple maintained below 100 mV RMS, independent of engine speed or load.

The control system integrates electronic engine speed control and ECU/PPU electronic control, with all solid-state components mounted on printed circuit boards for enhanced durability in military environments.