TM-9-2815-220-24 Maintenance Manual for AVDS-1790-2CA AVDS-1790-DA and AVDS-1790-2DR Engines Download
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TM 9-2815-220-24 THEORY OF OPERATION 0004 00 ENGINE COMPONENTS (Continued) Generator: The generator changes the mechanical energy of the diesel engine into electrical energy. There are two different generators used on the AVDS-1790-2 Series engine. Both are 28-volt dc generators, one is rated at 300 amperes and the other is rated at 650 amperes. All Model 2CA engines are equipped with the 650-ampere model. All Model 2DR engines are equipped with the 300-ampere model. All Model 2DA engines are equipped with the 300-ampere model in their original configuration. However, some models, when used on the Armored Vehicle Launched Bridge (AVLB), have been upgraded to the 650-ampere generator. The 650-ampere generator is an oil-cooled, brushless, direct-current type (the generator generates an alternating current which is rectified within the unit to produce a direct current). The generator uses filtered oil from the engine main gallery line for cooling. Oil circulation is provided by a pump integral within the generator and equipped with an appropriate by-pass valve to limit oil pressure and flow. The generator is completely enclosed and waterproofed and will function equally well in or out of water. Air Out Air In The 300-ampere generator is an air-cooled, six-pole, six-brush, direct-current type. It is equipped with radio noise suppression capacitors for protection of nearby communications equipment. A blower motor mounted on the generator draws cooling air from the crew compartment through the air intake tube. This tube extends along the crankcase below the intake manifold on the right side of the engine. The generator cooling air exhaust tube is connected to the engine cooling shroud and exits through the rear cooling fan vane. A fording valve is available to render the generator air system water tight for deep water fording. A vehicle mounted voltage regulator controls generator output. WP 0004 00-22