AirLink MG90 Hardware User Guide
Rev 3 Feb.17
17
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Ground the MG90 Chassis
For DC installations (with a fixed “system” ground reference), Sierra Wireless strongly
recommends always grounding the MG90 chassis to this system ground reference.
To ensure a good grounding reference connect one end of a short 18 AWG or larger
gauge wire with a ring terminal connector to the ground terminal on the rear panel of
the MG90 and connect the other end to the vehicle chassis.
The ground terminal requires an M4x6 mm screw (or longer, depending on the ring
terminal connector size.)
Figure 2-5: Ground Connector (Rear Panel)
Cabling—Best Practices
Separate MG90 antenna, data, and power cables from other wiring in the vehicle and
route away from sharp edges.
Cable Strain Relief
Sierra Wireless recommends using cable strain relief for installations in high-vibration
environments.
Place the cable strain relief within 200 mm (8") of the MG90 to reduce the mass of
cable supported by the power connector under vibration. Ideally, the strain relief
mounting for the DC cable should be attached to the same object as the MG90, so
both the router and cable vibrate together. The strain relief should be mounted such
that it does not apply additional stress on the power connector (i.e. the cable should
not be taut and should not pull the power connector at an angle).
Cable Management
Proper cable management eliminates unnecessary installation complications, allows
for ease of maintenance, and prolongs cable longevity.
Ground
