TM 5-3805-260-24ELECTICAL SYSTEMThe electrical system has three separate circuits:the charging circuit, the starting circuit and the lowamperage circuit. Some of the electrical systemcomponents are used in more than one circuit. Thebattery (batteries), circuit breaker, ammeter, cables andwires from the battery are all common in each of thecircuits.The charging circuit is in operation when theengine is running. An alternator makes electricity for thecharging circuit. A voltage regulator in the circuit controlsthe electrical output to keep the battery at full charge.The starting circuit is in operation only when the startswitch is activated.The low amperage circuit and the chargingcircuit are both connected to the same side of theammeter. The starting circuit connects to the oppositeside of the ammeter.SYSTEM COMPONENTSAlternator (Prestolite) 2P1204The alternator is driven by V type belts from thecrankshaft pulley. It is a 24 volt, 19 ampere unit with aregulator which has no moving parts (solid state)installed on the side opposite the pulley. The alternatoris made up of the following parts: head assembly on thedrive end, rotor assembly, stator assembly, rectifier andheat removal assemblies, brush and holder assembly,head assembly on the ring end, and regulator.The alternator has diodes which change thealternating current (AC) made by the alternator to directcurrent (DC). This direct current is used to makemagnet like lines of force in a space around the statorassembly (field current). The field current is controlledby the regulator.Alternator (Delco-Remy)The alternator is a three phase, self rectifyingcharging unit. The regulator for the alternator is part ofthe alternator. The alternator is driven from thecrankshaft pulley by two V type belts.The only part in the alternator which hasmovement is the rotor. The rotor is held in position by aball bearing at the drive end and a roller bearing at therectifier end.The compartment for the regulator is sealed.The regulator controls the alternator output according tothe needs of the battery and the other components in theelectrical system.Starting MotorThe starting motor is used to turn the engineflywheel fast enough to get the engine running.STARTING MOTOR1. Field. 2. Solenoid. 3. Clutch. 4. Pinion.5. Commutator. 6. Brush assembly. 7.Armature.The starting motor has a solenoid. When thestart switch is activated, electricity from the electricalsystem will cause the solenoid to move the starter pinionto engage with the ring gear on the flywheel of theengine. The starter pinion will engage with the ring gearbefore the electric contacts in the solenoid close thecircuit between the battery and the starting motor. Whenthe start switch is released, the starter pinion will moveaway from the ring gear of the flywheel.2-19
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