Installation Manual

Electrical & Electronic Application And Installation Manual
Production Release Version 1.0
Page 62
carrying small signal currents. In particular, high current and signal wires
should not run parallel in the same harness bundle for any significant
distance. Ideally, if high current wires must be in proximity to signal wires then
they should cross at right angles.
The engine wire harness should not be used by the installer as a support for
any components that are not supplied as part of the engine system. For
example, external hoses and wires should not be tied to the engine harness.
Care should be taken during design to ensure that components are accessible
for repair and possible replacement in the field. Poor maintenance access
may lead to poor quality repairs in the field.
Routing of machine side control signal cables must be designed such that a
minimum clearance of 25mm to any engine fuel filter bowl is maintained, to
protect against the potential for electrostatic discharge effecting operator
controls.
5.8.4 Electromagnetic Compatibility (EMC)
Special measures should be taken to shield cables if the application is to be
used in extreme electromagnetic environments – e.g. aluminum smelting
plants.
If screened cables are used, the screens should be connected to ground at
one point only. That point should be central if possible.
In some cases an optional engine electric fuel lift pump ferrite may be required
to help machine EMC certification. The Perkins supplied ferrite part number is
472-0078.
5.8.5 Insulation Selection and Thermal Protection
Care must be taken when routing the underhood electrical cabling to ensure
that it is routed away from any hot objects such as the engine turbo and
exhaust as well as the engine aftertreatment. In some cases this may not be
possible in which case care must be taken to ensure that the cable insulation
used is rated to the areas in which it is routed. In some cases specialist
insulation maybe required such as Teflon etc.
It should also be noted that high temperature cables do in many cases have a
reduced overall diameter when compared to GXL cable. If this is the case
then an analysis of the connector sealing capabilities must be undertaken to
ensure that each connector seal maintains its sealing capabilities.