LMU 3640 Installation Guide
Preparing for Installation
Be sure you have received all the LMU components you need. This must include:
The LMU to be installed
A power harness
GPS Antenna (for external devices)
Comm Antenna (for external devices)
Optional Components:
Input and output cables
Relays
LMU peripherals (i.e. Serial adapter, jPOD, TetheredLocator)
Host serial devices (e.g. PDAs, laptops, other serial devices)
Plan The Installation
Verify Power, Ground and Ignition. Be sure to check each source (power, ground and ignition) to ensure that the proper signaling exists. This is typically accomplished with a multi-meter.
Before drilling any holes or running any wires, decide where each hardware component will be located (LMU, antennas, peripherals, etc.). Be sure that the cables to the LMU are not bent or constricted in any way. Also make sure that the LMU is kept free from direct exposure to the elements (sun, heat, rain, moisture etc...).
Be advised that an installation that violates the environmental specifications of the LMU will void the warranty.
The best way to ensure a trouble-free installation is to consider your options and make some decisions before you start. Take a look at the vehicle and determine how to best install the LMU for the following purposes:
Accurate data gathering and simulation of how customers actually use your solution
Ongoing monitoring and maintenance of LMU equipment
Accidental or intentional alteration of the equipment or cable connections
The following sections cover some of the issues to consider when planning your LMU installation.
Size and Placement of LMU Unit
The dimensions of the LMU should be taken into account, particularly when installing in a vehicle:
Whether you intend to place the LMU under a seat or into a cavity behind the vehicle’s interior molded trim, be sure the LMU will fit before drilling any holes or running cable
Be certain that the cables running to the LMU will not be bent or constricted. Damage to the cables may impede the LMU’s performance.
Be certain that the installation point will not violate any of the LMU’s environmental specification (temperature, moisture, etc…) as improper installation of the LMU may void the warranty.
See the LMU Environmental Specifications for the exact measurements and specifications of the LMU-3640™.
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.
Access to the SIM (Subscriber Identity Module) Card
When used in a LTE or HSPA, 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.
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.
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.
Cable Length
Do not cut cables. Instead, coil any excess length, making sure not to crimp or flatten any cable.
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.
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.
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:
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.
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 commercial wiring practices to create a permanent installation rather than using press-in fuse clips or other temporary measures.
DO NOT connect the power cable to the LMU at this time.
Typical Connection Sequence
Connect any peripherals to the LMU
Plug in the power harness.
The physical installation of the LMU hardware is now complete.
Installation Verification
In many cases it is desirable to verify that an installed LMU-3640™ is working properly. That is, installers should verify that the GPS and communications functions of the LMU-3640™ are working properly before departing the installation site. In more robust cases, some key configuration settings such as the Inbound Address and URL should also be verified.
Note that these processes are all based on issuing AT Commands to the LMU-3640™. It is expected that installers will have access to a serial port expansion cable and a laptop or PDA capable of a terminal connection. Alternatively, an SMS message can be sent to an LMU-3640™ to obtain its current status.