TM 9-2320-392-10-1
M1083A1 SERIES THEORY OF OPERATION - Continued 0003 00
ELECTRICAL SYSTEM-Continued
Alternator, Battery, and Starting Systems (Vehicle S/N 18,550 to 199,999).
The vehicle Electrical System is a combined 12/24 VDC system. Four 12-volt batteries are
connected in series-parallel with the negative terminal grounded to the vehicle chassis.
1.
Positioning the master power switch to on applies power to all electrical circuits
needed to operate the vehicle.
2.
The starting motor operates directly from the 24 VDC source through the starter
pushbutton.
3.
A Dual-Voltage, 100 Amp belt-driven alternator maintains the charge on the
batteries. This alternator can operate without the batteries, and provides a trickle
charge to the batteries while they are disconnected. The alternator also includes
two on-board LED's one for the 12 VDC output and one for the 24 VDC output. See
Table 1. Alternator LED Status for more information. The 24 VDC source supplies
electrical power to operate the starting motor, Central Tire Inflation System (CTIS),
fuel/water separator, air dryer, ether injection system, instrument panel assembly
gages, windshield wipers/washer, and the Material Handling Crane (MHC). The 12
VDC source supplies electrical power to the vehicle lights and instrument panel
assembly lights.
Table 1 Alternator LED status.
LED COLOR
SYSTEM STATUS
Off
Regulator is not energized.
FLASHING
Green
The respective system voltage (12 or 24 VDC) is
normal.
Amber
The respective system voltage (12 or 24 VDC) is
low.
Red
The respective system voltage (12 or 24 VDC) is
high.
STEADY
Red
The alternator is shut down and is not producing
power for either (12 or 24 VDC).
4.
The system monitors battery voltage and alternator performance. If the batteries
fail, the Load and Battery Control Device (LBCD) provides a ground to the battery
disconnect relay, disconnecting the batteries from the electrical system and
illuminating the BATTERY DISCONN indicator on the lighted indicator display. The
vehicle continues to run off the alternator, and a trickle charge is provided to the
batteries. Once the batteries reach an acceptable voltage level, the LBCD removes
the ground from the battery disconnect relay, and the batteries are reconnected to
the electrical system. If the alternator fails, the LBCD illuminates the CHARGING
SYSTEM indicator on the lighted indicator display.
0003 00-18
