The "G120 Iridium Harness" provides an introduction to installing the supplied harness by Digital Matter for the G120 Iridium module. 

This article covers the crucial hardware components needed to set up and operate the G120 with the Iridium Edge Module. 

The goal is to provide you with an exhaustive guide, detailing every required component for a smooth setup process. 

Required Components for Iridium Operation

1. G120 Device (supplied by DM)
2. Dedicated G120 Iridium Harness (Supplied by DM or build your own)
3. Iridium Edge Module - not supplied by DM, can be sourced via other suppliers 
4. Iridium Data Plan 

Iridium Edge Module

The Iridium Edge module plays a pivotal role in extending the G120's tracking capabilities globally. This module, which functions both as a modem and an antenna, facilitates communication with the Iridium satellite network, offering comprehensive L-band voice and data coverage.

• Connection
  • For the G120, the module is connected via an Iridium harness utilizing the RS232 protocol. The standard G120 harness includes the RS232 interface wires.
• Power Requirements
  • It is important to note that the Iridium Edge requires an external power source of 9-32V and cannot rely on the G120's internal battery for operation.

Integrating the Iridium Edge Module with the G120 ensures that your device remains connected for tracking purposes, even in locations without cellular coverage.

Mounting the Iridium Edge: 

The Iridium Edge needs to be mounted with a clear view of the sky. For the G120, ensure the harness is long enough to allow this positioning. A length of approximately 2 meters between the G120 and the Iridium Edge should suffice for most vehicles.

Build your own Iridium Harness

To create your own harness for the G120, you will need to source a female M12-8 connector. This is essential for establishing a connection with the device.

IP67 Rating: It's important that the female connector sourced for the G120 is IP67 rated. This ensures that the integrity of the IP67 rating is maintained across the connection with the Iridium Edge.

The G120's Iridium compatibility involves a plug-and-play DM Iridium harness that starts with the standard 24-way molex, connecting to the Edge Module via an M12-8 connector. It includes specific wiring for power, RS232 communication, and device control, emphasizing the G120's capability to operate as a hybrid Iridium device with direct power connection requirements for the Iridium Edge.

G120 Harness connector	Iridium Module Connector - M12-8

• Power on Iridium Edge is a separate red wire that is bundled with the G120 to Iridium Edge cable and needs to be connected directly to           power as well as the G120 Vin
• RS232 RX (pin 22 on G120)
• RS232 TX (pin 21 on G120)
• GND (taken back to G120 GND)
• SW GND (pin 11 on G120) - controls on/off of Edge

The pinout for the Iridium Edge connector (looking into the connector) is as follows.

The numbers in brackets relate to the G120 pin. This can be found in the article for the G120 Harness definition.