Komatsu 830E-AC Shop Manual page 433

AC DRIVE SYSTEM ELECTRICAL CHECKOUT PROCEDURE
AC DRIVE SYSTEM MAINTENANCE
DANGEROUS VOLTAGE LEVELS ARE PRESENT
WHEN THE ENGINE IS RUNNING AND CONTINUE
TO EXIST AFTER SHUTDOWN IF THE REQUIRED
SHUTDOWN PROCEDURES ARE NOT FOLLOWED.
Before attempting repairs
propulsion system components, the following
precautions and truck shutdown procedure must
be followed:
•
DO NOT step on or use any power cable as a
handhold when the engine is running.
•
NEVER open any electrical cabinet covers or
touch the Retarding Grid elements until all
shutdown procedures have been completed.
•
ALL removal, repairs and installation of
propulsion system electrical components,
cables etc. must be performed by an electrical
maintenance technician properly trained to
service the system.
•
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 insulation prior to
servicing the cables and prior to returning the
truck to service. Discard cables with broken
insulation.
•
IN THE EVENT OF A PROPULSION SYSTEM
MALFUNCTION, a qualified technician should
inspect the truck and verify the propulsion
system does not have dangerous voltage
levels present before repairs are started.
E03018 10/06
or working near
After the truck is parked in position for the repairs, the
truck must be shut down properly to ensure the safety
of those working in the areas of the deck, electrical
cabinet, traction motors, and retarding grids. The
following procedures will ensure the electrical system is
properly discharged before repairs are started.
If a problem occurs in the AC drive system that
prevents use of normal shutdown procedures,
ADDITIONAL PRECAUTIONS ARE NECESSARY to
ensure that dangerous drive system voltages are
not present when tests or repairs are performed.
AC Drive System Electrical Checkout Procedure
(Release 21 Software)
•
If weld repairs are required, the welding
ground electrode should be attached as close
as possible to the area to be welded. NEVER
weld on the rear of the Electrical Control
Cabinet or the retard grid exhaust air louvers.
Power cables and wiring harnesses should be
protected from weld spatter and heat.
•
Prior to welding, disconnect Engine Control
System (ECS) harnesses and ground wire
(MTU engine). If equipped with DDEC or
Komatsu engine, disconnect ECM harnesses.
GE cards should be pulled forward far enough
to disconnect card from backplane connector.
•
Some power cable panels throughout the
truck are made of aluminum or stainless steel.
They must be repaired with the same material
or the power cables may be damaged.
E3-3