Installation Guide

Typical installations will place the LMU under the vehicle dash board, or in the trunk. Make sure you can get access to the unit
afterwards as
under some circumstances it may be necessary to add additional wiring or connections to the LMU.
5.4.2 Access to the SIM (Subscriber Identity Module) Card
When used in a LTE, each LMU uses a Subscriber Identity Module (SIM) card, which should be inserted before you install the
LMU for the first
time. The SIM card is attached to the main-board inside the housing of the LMU unit.
At some future time, you might need or want to replace the SIM card with a different one, so try to install the LMU in such a way
that the cover
can be removed to make the SIM card accessible.
5.4.3 Protection from Heat
It is best not to place the LMU unit in an unusually warm location such as directly near heater vents, near hot engine components
or in direct
sunlight. The maximum temperature that can be tolerated by the LMU is described in the LMU Environmental Specifications
section.
5.4.4 Visibility of Diagnostic LEDs
Status LED lights on the front of the LMU unit can provide valuable information about the operation of the LMU. When feasible,
attempt to
install the LMU in such a way that these lights can be seen with reasonable ease.
You may find it useful to be able to view the LEDs periodically to make sure that the LMU is operating properly. If at any time
you should
encounter a problem with the LMU, you may need to read the LEDs in order to troubleshoot the problem. If you cannot fix the
LMU yourself, you
will need to provide the LED information to CalAmp customer support.
For information about how to interpret the LEDs, see the Status LED Behavior section.
5.4.5 Cable Length
Do not cut cables. Instead, coil any excess length, making sure not to crimp or flatten any cable.
5.4.6 Moisture and Weather Protection
The LMU unit must be located where it will not be exposed to moisture or water. In a typical installation inside a vehicle this is
not commonly
thought to be a concern; however, it might be best to avoid locating the LMU below a car’s cup holders, or where rain might
easily splash into the
compartment when a door is opened.
5.4.7 Preventing Accidental or Unauthorized Modification
If you anticipate that fleet drivers or others might interfere with the LMUs once they are installed, take steps to be sure that it is
not easy to
remove the LMU from its power source, or disrupt internal antenna interference.
Two common methods are the use of Tamper Proof Sealant or creation of PEG Script to detect power loss or GPS antenna
disconnections.
5.5 Installing the LMU in a Vehicle
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This section provides instructions for installing an LMU in a vehicle.
Be sure to consider the design decisions described in the previous sections. When you are ready to begin installing the LMU,
follow these steps:
5.5.1 Place the HMU-3640 in the vehicle.
The HMU-3640 contains an internal battery, and thus should be oriented with the label facing upwards towards the sky. LMUs
with internal
antennas should be placed directly under a thick panel to maximize their performance and protect from external elements. A
typical location
include under the dash close to the front wind-shield.
Attach the LMU to the solid body of the vehicle, not to plastic panels. The LMU can be placed out of sight by removing interior
trim and molding
to expose available space, then replacing the trim once the LMU is in place.
5.5.2 Connect power, ignition, and ground.
The power input (red wire) must be connected to a constant (un-switched) +12 VDC or +24 VDC supply; preferably, connected
directly to the
vehicle battery terminal or as close to it as possible. This connection point should be fuse protected to not more than 5 Amps.
The ignition input (white wire) must be connected to the vehicle ignition or another appropriate key operated line, such as
ACCESSORY, ensuring
that power to the ignition wire is available only when the vehicle ignition is on.
The ground line (black wire) must be connected to chassis ground.