Service
Bulletin #1
EQUIPMENT GROUNDING
Field
Failure: The Power Touch
System tests OK in the shop, but out in the field the entire system may turn
itself off under heavy use.
Cause: The Ground path
from PDC-12 back through the toolbox to the C Rail Frame and battery Neg. was
inadequate.
Diagnosis: The PDCs were grounded to the toolbox that is mounted with
brackets to the vehicle cross members which are then attached to the C Rail
Frame. This multitude of daisy chained
mechanical connections provides too many opportunities for vibration, and
moisture, to eventually develop corrosion inside the assembled hardware until
the electrical connection fails. This
practice provides a predictably unreliable electrical ground return for the
vehicles electrical system. The
electrical equipment is designed to operate with 12vDC and will operate
reliably with supply voltages between 10.5v - 14.5v. If poorly grounded, the voltage available to
the equipment will decrease as the load current increases until this low
voltage threshold is crossed and the equipment stops working.
Field Service:
Customer installed a ground cable directly from the GND stud inside the PDC-12
to the C Rail frame.
Recommended Corrective Action: During installation of all PowerUp
electrical equipment a proper electrical ground, independent of the mechanical
ground, shall be installed. A single
ground needs to run from the GND post inside the equipment to the drivers side
C Rail through a proper wire gauge for the the product. The ground cable
connectors shall only be crimped with an approved ratcheting crimp tool
specifically designed for the size wire and connector used. The connection to
the frame will be made with a properly tensioned nut and bolt to clean bare
metal or to a similarly clean welded stud.
Power Up Products