Special Precautions For Working On A 830E-Ac Truck - Komatsu 830E-AC Shop Manual

SPECIAL PRECAUTIONS FOR WORKING ON A 830E-AC TRUCK

Preliminary Procedures before Welding or Per-
forming Maintenance
Prior to welding and/or repairing a 830E-AC dump
truck, maintenance personnel should attempt to
notify a Komatsu service representative. Only quali-
fied personnel, specifically trained for servicing the
AC drive system, should perform this service.
If it is necessary to perform welding or repair to the
truck without the field engineer present, the following
procedures should be followed to ensure that the
truck is safe for maintenance personnel to work on
and to reduce the chance for damage to equipment.
Anytime the engine is operating:
• DO NOT open any of the cabinet doors or
remove any covers.
• DO NOT use any of the power cables for hand
holds or foot steps.
• DO NOT touch the retarding grid elements.
Before opening any cabinets or touching a grid
element or a power cable, the engine must be
shutdown and the red drive system warning
lights must not be illuminated.
A3-18
Engine Shutdown Procedure before Welding or
Performing Maintenance
Normal operation of the drive system at shutdown
should leave the system safe to maintain. However,
in the event of a system failure, performing the fol-
lowing procedure prior to any maintenance activities
will ensure that no hazardous voltages are present in
the AC drive system.
General Safety and Operating Instructions
1. Before shutting down the engine, verify the sta-
tus of all the drive system warning lights on the
overhead display panel. Use the lamp test
switch to verify that all lamps are functioning
properly.
If any of the red drive system warning lights
remain on, DO NOT attempt to open any cabi-
nets, disconnect any cables, or reach inside the
retarder grid cabinet without a trained drive sys-
tem technician present - even if engine is off.
Only qualified personnel, specifically trained for
servicing the A-C drive system, should perform
this service.
2. If all red drive system warning lights are off, fol-
low the "Normal Engine Shutdown Procedure".
3. After the engine has been off for at least five
minutes, inspect the link voltage lights on the
exterior of the main control cabinet and rear of
the center console. If all lights are off, the retard
grids, wheel motors, alternator, and related
power cables are safe to work on.
4. Locate the GF cut-out switch in the access
panel on the left side of the main control cabi-
net. Place the switch in the CUTOUT position.
This will prevent the alternator from re-energiz-
ing and creating system voltage until the switch
is returned to the previous position.
5. Before welding on the truck, disconnect all elec-
trical harnesses from the Engine Control Sys-
tem (ECS) inside the electrical cabinet behind
the operator's cab. Also, disconnect the ground
strap from the ECS.
3/06 A03030