Handling Of Electrical Equipment - Komatsu PC88MR-10 Shop Manual

Handling of electrical equipment

To maintain the performance of the machine over a long period, and to prevent failures or troubles before
they occur, correct "operation", "maintenance and inspection" "troubleshooting", and "repairs" must be
performed. This section deals particularly with correct repair procedures for mechatronics components
and is aimed at improving the quality of repairs. For this purpose, it describes the working procedures in
"Handling of electrical equipment".
Precautions for handling electric equipment
Handling wiring harnesses and connectors
Wiring harnesses consist of wires connecting
one component to another component,
connectors used for connecting and
disconnecting one wire from another wire, and
protectors or tubes used for protecting the wires.
Compared with other electrical components
fitted in boxes or cases, wiring harnesses are
more likely to be affected by the direct effects of
rain water, heat, or vibration. Furthermore,
during inspection and repair operations, they are
frequently removed and installed again, so they
are likely to suffer deformation or damage. For
this reason, it is necessary to be extremely
careful when handling the wiring harnesses.
Main failures occurring in wiring harness
Defective contact of connectors (defective
contact between male and female connectors)
Problems with defective contact are likely to
occur because the male connector is not
properly inserted into the female connector,or
because one or both of connectors are
deformed or the position is not correctly aligned,
or because there is corrosion or oxidization of
the contact surfaces. The corroded or oxidized
contact surfaces may become shiny again (and
contact may become normal) by connecting and
disconnecting the connectors approximately 10
times.
PC88MR-10
Foreword, safety and general information
(ALL-E000-2A4-P-01-A)
Defective crimping or soldering of connectors
The pins of the male and female connectors are
attached to wires by crimping or soldering. If
excessive force is applied to the wire, the joining
area may become loose, which may result in a
defective connection or breakage.
Disconnections in wiring
If the wiring harness is pulled to disconnect the
connector, or the components are lifted with a
crane while the wiring harness is still connected,
or a heavy object hits the wiring harness, the
crimping of the connector may separate, or the
soldering may be damaged, or the wiring
harness may be broken.
00 Index and foreword
(Rev. 2012/11)
00-31