TM-9-2350-311-20-1 Maintenance Manual for Volume 1 M109 Hull Download
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TM 9-2350-311-20-1 1-11 NUCLEAR HARDNESS Not applicable. 1-12 SECURITY MEASURES FOR ELECTRONIC DATA Not applicable. SECTION Il. EQUIPMENT DESCRIPTION AND DATA 1-13 CAPABILITIES AND FEATURES NOTE Refer to TM 9-2350-311-10 for further equipment description and data. 1-13.1 Electrical System M109A2/M109A3/M109A4/Ml109A5 Howitzers’ electrical power is provided through a 24-Vdc (nominal) generating system consisting of the following components (Chap 8): a. Four 12-Vdc (nominal) batteries connected in series/parallel that provide 24 Vdc (nominal) to the master relay. b. M109A2/M109A3 Howitzers have 3-phase, 100-amp alternator that maintains 24-Vdc (nominal) electrical power through the voltage rectifier, voltage regulator, and to the master relay for systems operation. M109A4/ M109A5 Howitzers have a 3-phase, 180-amp alternator. c. Master relay that delivers electrical power to electrically operated systems/equipment in M109A2/M109A3/ M109A4/M109A5 Howitzers (hull and cab) by turning on the MASTER switch. The MASTER switch, located on the driver’s portable instrument panel, actuates the vehicles’ electrical system. With the powerplant off (engine not running), activation of the MASTER switch provides delivery of electrical power direct through the alternator, voltage rectifier, voltage regulator, and master relay circuit. 1-13.2 Powerplant (Engine and Transmission) The powerplant (engine and transmission) provides the mobility for M109A2/M109A3/M1 09A4/M109A5 Howitzers. The powerplant consists of the following subsystems: a. Two engines are available: • Detroit Diesel 8V71T, model 7083-7396, diesel, liquid-cooled, V-8 engine, which generates 405 horsepower at 2300 rpm. • Detroit Diesel 8V71T, model 7083-7391, diesel, liquid-cooled, V-8 engine, which generates 440 horsepower at 2300 rpm. 1-9