Battery Boost Adjustment; Isolation Amplifier & Voltage Module Test; Voltage Measuring Module Test (Vmm1 & Vmm2) - Komatsu 830E Shop Manual

8.5 Battery Boost Adjustment

1. Turn On key switch and control power. Start engine and place selector switch in NEUTRAL.
2. Setup the PTU to read values on the AUTOMATIC LOAD BOX TEST SCREEN.
3. Connect voltmeter to R1 battery boost resistor, 74C (+) and 74AA (-).
4. Depress the override switch to clear any faults. If necessary, clear event codes on 2 digit dis-
play.
5. Place the selector switch in FORWARD. Slowly depress accelerator.
Observe +15 to +20 volts at R1 as engine rpm increases from low idle speed.
Verify R1 voltage drops to 0.0 volts as the engine begins to load (approximately 800 to
1000 rpm). Adjust Pot P1 on AFSE panel if necessary
Verify positive (+) values for MOTOR 1 & 2 AMPS, MOTOR FIELD AMPS, and ALTER-
NATOR VOLTS on PTU screen.
6. Seal pot adjustment screw when completed.
7. Place selector in NEUTRAL and shut down engine. Remove voltmeter.
8. Exit back to the GEOHV STATEX III MENU screen.
8.6 Isolation amplifier & voltage module test.
NOTE: If there is a discrepancy with the card test procedure results, consult the appropriate GE
Publication.
The system utilizes two types of Isolation Amplifiers (Iso-Amps). Two are used for voltage measure-
ment (VMM1 and VMM2). The other six are used for current measurement (ISOA-3, ISOA-4, ISOA-
5, ISOA-6, ISOA-7, and ISOA-8).
8.6.1 Voltage Measuring Module Test (VMM1 and VMM2)
NOTE: There are two recommended test procedures for testing the 17FM458 Voltage Measuring
Module. One test requires the use of a high voltage power supply and can be found in the
17FM458 Instruction Book and all appropriate Vehicle Test Manuals. The alternate test method is
detailed below.
1. Disconnect 74C at GFR relay.
2. Disconnect the wires from terminals "A" and "C".
3. Turn On control voltage (B+).
Verify +15V on terminal "G" and -15V on terminal "E."
Measure and record B+ voltage on wire 71.
4. Connect a voltmeter from terminals "D" (+) to "F" (-).
5. Jumper terminals "C" to "F" and terminals "A" to "F".
Verify 0.00 ±.02V on the voltmeter.
6. Remove jumper from terminals "A" to "F".
7. Jumper terminal "A" to B+.
Verify voltmeter reads (B+) ÷ 200, ±2%.
Example: If B+ = 25v, the voltmeter should read: 25 ÷ 200 = 0.125 ±0.0025 volts.
8. Turn off control power, disconnect voltmeter and jumpers and reconnect all wiring to the panel.
E3-44 Statex III Electrical Checkout Procedure 2/02 E03012