21kW Auxiliary Power Unit (APU) For M109 Howitzer

A modular 21kW Auxiliary Power Unit (APU) with 28VDC 270A brushless alternator to:

• Supply 28VDC, 120A to charge the vehicle batteries or supply the total electrical requirement of the turret including a possible WMS system, without starting the vehicle main engine.
• Supply 28VDC, 110A for the air conditioning system.
• Belt drive the 12kW ACU compressor.

The APU/ACU system does not restrict the standard operational features of the vehicle in terms of firing and mobility. It has its own 28V 120Ah battery pack and 80 litre fuel tank on board. The electrical connections, looThe APU/ACU system does not restrict the standard operational features of the vehicle in terms of firing and mobility. It has its own 28V 120Ah battery pack and 80 litre fuel tank on board. The electrical connections, looms between the aircon, power units, electronic control panels and electrical control gear are designed and selected for operation in military environments, which include adverse temperatures as well as severe shock and vibration.

The aircon and power units are equipped with custom designed electronic controllers, capable of all control and safety functions. The controller automatically regulates the engine speed according to load to conserve fuel, reduce noise and prolong engine life. The system has a Bluetooth login interface for remote monitoring via a smartphone app and/or laptop. Installation of the units requires minimal vehicle modifications. Modules are mounted on the outside on the rear of the turret in such a way that personnel actions and movement are unaffected.