Komatsu 930E-2 Shop Manual page 33

for servicing the AC Drive System, should
perform this service.
2. If all red drive system warning lights are off, follow
the "Normal Engine Shutdown Procedure".
3. After the engine has been stopped for at least five
(5) minutes, inspect the LINK VOLTAGE lights on
the exterior of the main control cabinet and back
wall of the operator's cab (DID panel). If all lights
are OFF, the retard grids, wheel motors, alterna-
tor, and power cables connecting these devices
are safe to work on.
4. Locate the "GF" Cut-out switch in the access
panel on the left side of the main control cabinet.
Place the switch in the "Alternator Cutout" posi-
tion. This will prevent the alternator from re-ener-
gizing and creating system voltage, until the
switch is returned to its former position.
5. The blower motors, control cabinet and power
cables connecting these devices are still unsafe.
To establish that these devices are safe, open the
top control cabinet cover and inspect the red
lights on the blower control panel.
If these lights are OFF, the blower system, blower
power cables, and remainder of the control cabi-
net is safe to work on.
If these lights are ON, refer to steps 11 – 12.
6. Before welding on the truck, disconnect all elec-
trical harnesses from the Engine Control System
(ECS) inside the electrical cabinet behind the
operator's cab (disconnect left one first). Also,
disconnect the ground strap from the ECS.
7. Do not weld on the rear of the control cabinet!
The metal panels on the back of the cabinet are
part of capacitors and cannot be heated.
8. Do not weld on the retard grid exhaust louvers
- they are made of stainless steel. Any welding
done here must be done by qualified welders,
using the appropriate equipment and materials.
Some power cable panels throughout the truck
are also made of aluminum, or stainless steel.
They must be repaired with the same material, or
the power cables may be damaged.
9. Power cables must be cleated in wood or other
non-ferrous materials. Do not repair cable cleats
by encircling the power cables with metal clamps
or hardware. Always inspect power cable insula-
tion prior to servicing the cables and prior to
returning the truck to service. Discard cables with
broken insulation.
A03017
10. Power cables and wiring harnesses must be
11. If the red lights on the exterior of the control
12. If the red lights on the blower control panel are
13. Replace all covers and doors and place the "GF"
General Safety and Operating Instructions
protected from weld spatter and heat.
Always fasten the welding machine ground (-)
lead to the piece being welded; the grounding
clamp MUST BE ATTACHED AS NEAR AS
POSSIBLE to the weld area.
Always avoid laying welding cables over or near
the vehicle electrical harnesses. Welding voltage
could be induced into the electrical harness and
possibly cause damage to components.
Before doing any welding on the truck, always
disconnect the battery charging alternator lead
wire and isolate electronic control components
before making welding repairs.
In addition, always disconnect the positive and
negative battery cables of the vehicle. Failure to
do so may seriously damage the battery and
electrical equipment.
Never allow welding current to pass through
ball bearings, roller bearings, suspensions, or
hydraulic cylinders.
cabinet and/or the back wall of the operator's cab
continue to be illuminated after following the
above procedure, a fault has occurred.
Leave all cabinet doors in place, do not touch the
retard grid elements, do not disconnect any
power cables, or use them as hand or foot holds.
Notify the Komatsu factory representative im-
mediately. Only qualified personnel, specifi-
cally trained for servicing the AC Drive
System, should perform this service.
illuminated after following the above procedure, a
fault has occurred. Reinstall the control cabinet
panel. Do not perform maintenance on the blower
control panel or blower motor power cables.
Notify the Komatsu factory representative im-
mediately. Only qualified personnel, specifi-
cally trained for servicing the AC Drive
System, should perform this service.
cutout switch and battery disconnect switches in
their original positions, and re-connect all har-
nesses prior to restarting the truck.
Leave the drive system in the REST position until
the truck is to be moved.
A3-19