DIAGNOSTIC STATUS CODES
IT TRANSISTOR CONTROL
Page
17
Figure 2
5.
Reconnect
plugs.
Reference
Cleaner Chemtronics
Pow-R-WasH CZ
Contact Cleaner
Lubricant Nye
Lubricants NYOGEL
760G
GE Plug Lub Kit Contains both above products:
328A1777G1
Section 4.4 Controller Mounting Guidelines
In the design of the GE family of motor controls,
performance assumptions were made based on heat
transfer between the control and the ambient
environment. The vehicle mounting surface acts as a
heat sink, which increases the effective surface area
for heat dissipation. If this assumed heat transfer is
not achieved during control installation and operation,
GE controllers will fall short of their anticipated
performance. It should be noted that the condition of
the mounting surface, and the quality of the resulting
interface between the control and the vehicle, can
significantly hinder heat transfer from the control.
The presence of contaminants, or of air voids created
by surface inconsistencies in either the vehicle or the
control, degrade the control’s capacity for heat
transfer. The control’s performance is de-rated
proportionally as its own thermal sensors reduce its
operation to protect it from damage due to excessive
heating.
Contained within the software of the GE controls are
several diagnostic status codes related to controller
thermal performance. Failure to follow these
mounting recommendations increases the likelihood
of encountering these status codes, through no fault
of the control itself, thus voiding controller warranty
for units returned solely due to the presence of these
status codes.
Careful surface preparation, including adequate
application of thermal compound, as detailed in the
following paragraphs, must be completed during the
installation of GE controls. There are many
techniques for applying thermal compound, and we
have outlined one approach below that has shown to
apply a consistent thickness of material.
Section 4.4.1 Necessary Tools
GE recommends the use of the following
components, or equivalent substitutions, during the
control installation process:
a) Thermal compound, (Dow Corning
#340), maintained per the manufacturer’s
recommendations and free of
contaminants
b) 3/32” notched trowel, such as a Krusin
adhesive spreader, model 00031
c) Calibrated torque wrench (0 – 15 ft-lbs)
Section 4.4.2 The GE Control Mounting Surface
During the manufacture of the GE control, the
surface flatness is maintained at 0.005” per linear
inch (not to exceed 0.025” per 10.0 inches). The
surface finish of the GE control has an R
a
(average
roughness) of 64 (microinches), or better. This finish
is consistent with cold rolled or extruded aluminum.
Care should always be taken in the handling and
storage of controllers. The base of the control should
be free from nicks, bumps, protrusions or any other
foreign object that would prevent the control from
sitting flush with the vehicle mounting surface.
Examine the base of the control to verify that it is in
good condition and free from damage or
contamination.
Section 4.4.3
Vehicle Mounting Surface
November 2005
Nye
LU
BRI
CAN
TS
The quality of the vehicle mounting surface is critical
for the optimum heat transfer between the control
and the ambient environment. Conduction through
the base of the control is the control’s only means of
heat rejection. While GE controls are highly efficient,
a few percent of the electrical energy will be
converted into heat. As previously mentioned, if this
energy is not dissipated through the base of the
