Retard Speed Control System Check; Overspeed Pickup And Dropout Check - Komatsu 830E Shop Manual

5.0 RETARD SPEED CONTROL SYSTEM CHECK

Preparation and Setup
•
Disconnect external 77 and 714 wires (routed to the wheel motors) from control cabinet termi-
nal board.
•
Jumper 77 to 714, and jumper 77A to 714A.
•
Connect an oscillator to circuits 77 and 77A.
•
If truck is equipped with Two Speed Overspeed, remove and insulate wire 73LS routed to the
rear suspension pressure switches. Install a jumper between circuit 71 and 73LS on the control
cabinet terminal block to simulate an Empty Truck.
Setup PTU
1. With control power On, select "PTU TALK TO TRUCK" on GE OHV STATEX III PTU MAIN
MENU. Press [ENTER] key.
2. At "Enter your name:" type your name. Press [ENTER] key.
3. At "Enter your password:" type your password. Press [ENTER] key.
4. The GE STATEX III PTU MAIN MENU should appear on the screen.
5. Move cursor to select "NORMAL OPERATION". Press [ENTER] key.
a. A screen will appear that states: "Selection of NORMAL OPERATION gives truck control to
the driver. Continue?"
b. With the cursor next to "Yes", press [ENTER].
6. The NORMAL OPERATION MENU should appear on the screen.
7. Move cursor to select "RETARD STATE LOGIC". Press [ENTER] key.
8. The RETARD STATE LOGIC SCREEN screen should appear. Information on this screen will
be observed for the following tests.

5.1 Overspeed Pickup and Dropout Check

1. With control power On, place selector switch to FORWARD position, and place retard speed
control switch to Off position.
2. Increase oscillator frequency until Overspeed Pickup point is reached (RP1 and RP2 retard con-
tactors pick up and PTU SYSTEM STATE = changes to RETARD). Record MPH observed on
digital speedometer or PTU screen. Verify that this reading agrees with empty overspeed
detect mph setting recorded during Speed Event Checks from the OVERPSPEEDS ENTRY
SCREEN.
3. Lower the frequency until the retard contactors drop out. Verify this point is approximately 3
MPH below the Overspeed Pickup point and agrees with empty overspeed dropout mph set-
ting. Turn off oscillator, without disturbing frequency setting.
E03012 2/02 Statex III Electrical Checkout Procedure E3-37