D
ATA
M
AXX
A
DDITIONAL
I
NFORMATION
H
OW
TO
W
IRE
C
ORRECTLY
How you wire your
D
ATA
M
AXX
unit is one of the most critical and important steps in the installation
process. Sensor wires should be at least 8” away from any ignition component otherwise your signals
will be erratic and hard to read. Ignition components include ignition boxes, ignition coils, distributors,
magnetos, and even ignition kill switches. If possible you want to run your data cables together back to
the main and/or analog module as this will reduce the amount of noise we are susceptible to.
Almost every cable provided with your
D
ATA
M
AXX
has a shield (drain) wire. On the
D
ATA
M
AXX
Module
end of the cable, trim your cable insulation back about 3”, leaving all the wires and aluminum foil and
shield wire. Next, untwist and cut off the aluminum foil. You should have left the insulated wires plus
the bare shield wire.
Prepare the ends of each insulated wire and affix each under the appropriate screw terminal, leaving the
shield wire loose. Tinning each wire with solder before screwing it into the terminal will improve
reliability.
As the last step, loop the shield wire under one of the shield screws (near the cable entry). Pull the
shield wire so as to drag the sheathed cable right up against the screw terminal. Tighten the screw then
cut off the excess shield wire.
It is helpful to connect several cables without connecting the shield wires. Then, gather multiple shield
wires at once, twist them together, and pull the whole assembly under a shield screw.
When wiring an economy sensor that did not have a supplied cable, it is recommended to use a wire
between the gauges of 18 to 22.
A
VOIDING
RFI N
OISE
You may also need to worry about ignition noise affecting your main
D
ATA
M
AXX
unit. If you have a
hot
ignition with no resistance (solid core) in the coil or plug wires, then it is advisable to keep as great a
distance as possible between those wires and your
D
ATA
M
AXX
. In full bodied cars, if you can mount the
unit on the opposite side of a firewall, do so. In open bodied cars, the unit can be mounted in the very
rear or the very front. If using solid core wires, and noise is apparent, it is advisable to use MSD 8.5mm
Copyright c 2008 Computech Systems Inc. 40