CalAmp TTU-2830, Руководство по установке оборудования, Страница: 14 / 22

4.2.6 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 disconnect the antenna wiring, remove
the LMU from its power source, etc.
Two common methods are the use of Tamper Proof Sealant or creation of PEG Script to
detect power loss or GPS antenna disconnections.
5.Installing the LMU in a Vehicle
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:
5.1 Place the LMU unit in the vehicle.
Typically, the LMU should be placed under the passenger seat or dashboard of the
vehicle. LMUs with internal antennas should be placed to maximize their GPS
performance. 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.
5.2 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.
Failure to connect these lines in the manner described may result in discharge of the
vehicle battery.
For best results, it is strongly recommended that the LMU connection be on its own
circuit. Connect the power input directly to the vehicle battery if possible and protect the
circuit with an inline fuse. If you must connect through the fuse box, use standard