Vehicle Auxiliary Power Units

vehicle-aux-powerDewey offers APUs that are enclosed or open frame configured for vehicle installation.

Our APUs have been trailer mounted, vehicle mounted, and ground mounted in all possible environmental conditions. These units charge battery systems, pump fuel from remote fuel tanks, are airlifted into desert environments, and operate in extreme cold and heat to support military, border security, transportation, and government programs worldwide. Contact Dewey to see what we can design for you.

Enclosed Vehicle Power Supply (EVPS) 28V DC 4.5kW


The EVPS is a 4500W, 28V DC Auxiliary Power Unit (APU) designed and manufactured by The Dewey Electronics Corporation. The APU is designed to operate in parallel with the 24V Vehicle Power System or as an independent DC voltage source. The EVPS is powered by a one-cylinder, four-cycle, fuel injected, naturally aspirated, air-cooled diesel engine which occupies the front half of the generator set. The engine is capable of operating on DL-1, DL-2, or JP-8 fuel and has an MTBF that’s greater than 1000 hours. A safety device automatically stops the diesel engine during conditions of low engine oil pressure. The DC alternator is a two-pole, revolving field-type AC alternator rectified to DC. The alternator is coupled directly to the diesel engine crankshaft. Output voltage is controlled by a voltage regulator that is programmable to accommodate the charging of Hawker Armasafe and Optima AGM batteries.

4 kW 28V DC EVPS Features:

  • Three independent axis mounting
  • Electric fuel pump with 72-inch lift
  • Electric start off vehicle battery or NATO Slave Adapter
  • Designed for Mil-Std-810 Sand and Dust environments
  • Remote monitoring capable with optional remote control box
  • Simple controls
  • Tactical quiet operations

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5kW 240V AC Open Frame APU

5kW AC Open Frame APU

This basic open frame designed generator provides a stand-alone power source that is capable of being configured to provide 120V, 240V in single or three-phase outputs. The generator is configured with a self-charging on-board battery to electronically start the generator. It is equipped with an enhanced air filter system that allows operation in extreme sandy and dusty environments.

The unit has the following features:

  • AC-GFCI Breaker
  • Control Box with:
    • Run time meter
    • DC & AC volt meters
    • Frequency meter
    • Load meter
  • Electric self-bleeding fuel pump
  • Low oil shutdown
  • 1 - Class L receptacle

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In one application this APU sits atop a 2000-gallon ISO containerized fuel system that is air-lifted into location for vehicle refueling. The APU provides 230V AC single phase power to operate the fuel pumps and refuel military vehicles.


Logistic Vehicle Power Supply (LVPS) 28V DC 3.5kW

The LVPS APU was designed to vehicle-mount as part of an IED Defeat System that was deployed in Iraq to support the USMC. This open frame APU provided 28V DC power to charge a bank of Hawker Armasafe batteries that supplied power to the jammer system that was installed on the USMC Logistic Vehicle System.

The LVPS featured a current limiting voltage regulator, simple single switch operation, and a cable remote control box. The APU had an enhanced air filter system that successfully passed Mil-Std-810E, Method 510.3 Blowing Sand and Dust. When equipped with the Dewey-designed mounting feet, it successfully passed the 1000-mile transportation/mission road test per Mil-Std-810E, Method 514.4.

The LVPS features:

  • 3.5kW 28V DC @ 70°F, derated 3.0kW @ 130°F
  • Current limiting voltage regulator
  • Remote control box
  • Electric self-bleeding fuel pump


Power Output @ 95 °F Current Limiting Dewey Part Number
3.5kW 28V DC Voltage Regulator 70107-501

Download Data Sheet