Anti-Reversal Function (Ar) Check; Overspeed Retard Operation Check - Komatsu 830E Shop Manual

1.9 Anti-Reversal Function (AR) Check

•
Disconnect wheel motor speed sensor wires 77, 77A, 714 & 714A in control cabinet. Jumper
circuit 77 to 714. Jumper circuit 77A to 714A.
•
Connect an oscillator to circuit 77 and 77A at control cabinet terminal board. Do not turn oscil-
lator on.
1. Move Selector Switch to FORWARD. Depress throttle.
FORIN AS
a. Verify the feedback signal:
FORFB
2. Propulsion contactors MF, P1/(P2), GF, and GFR should energize.
MF P1 (P2) GF GFR
a. Verify the feedback signals:
MFFB P1FB (P2FB) GFFB GFRFB
3. Turn oscillator On and increase frequency until M1-SPD & M2-SPD reads 3 mph.
4. Move Selector Switch to REVERSE.
5. All contactors should drop out, Reverser should stay in forward position (to the right).
6. Release throttle and remove oscillator. Remove jumpers and reconnect speed sensor wires at
terminal board.
7. Reverser should shift to REVERSE position (to the left).
a. Verify the feedback signal:
REVFB
8. Move selector switch to NEUTRAL.

1.10 Overspeed Retard Operation Check

•
Disconnect wheel motor speed sensor wires 77, 77A, 714 & 714A at control cabinet terminal
board.
•
Jumper circuit 77 to 714, jumper circuit 77A to 714A on terminal board.
•
Connect an oscillator to circuit 77 and 77A at terminal board.
1. Move Selector Switch to FORWARD, and depress throttle.
FORIN AS
a. Verify the feedback signal:
FORFB
2. Propulsion contactors MF, P1/(P2), GF, and GFR should energize.
MF P1 (P2) GF GFR
a. Verify the feedback signals:
MFFB P1FB (P2FB) GFFB GFRFB
3. Increase the oscillator frequency until OVRSPD DIGITAL OUTPUT changes from off to = on,
which will indicate that overspeed condition has been obtained.
OVRSPD
E03012 2/02 Statex III Electrical Checkout Procedure E3-15