Sierra Wireless Airlink GX450, Hardware User'S Manual

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AirLink GX Series Hardware User Guide
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Pins 1 and 2
• Pin 1—VCC; Connect to +12 VDC (nominal) (red wire on DC cable)
• Pin 2—Ground; Connect to ground (black wire on DC cable)
Pin 3
This pin is the ignition sense pin (white wire on DC cable). The voltage level
present on this pin turns the device on and off.
Note: If you do not connect this pin to the ignition, you MUST connect it to the positive
terminal of your power supply or battery. The device looks for a qualified voltage on this pin
as part of the power up sequence (9
–
36 VDC). If one is not present, the device will not turn
on. If you are using a Sierra Wireless AC cable, the connection is inside the cable.
There are several typical connection options for this pin:
Option 1 — If you want the device turned on and off when the engine is
turned on and off:
· Connect pin 3 to the ignition
· In ACEmanager, disable the Low Power Mode (Default setting is disabled)
Option 2 — If you power the device from the engine’s battery and you do not
want the device to drain it when the engine is turned off:
· Connect pin 3 to the ignition
· In ACEmanager, enable the Low Power Mode and set a time delay
When the ignition is turned off, the device operates at full power for the pro-
grammed time delay. When it expires, the device switches to Low Power Mode
(consumes 35 mA or less). The device resumes normal operation when the
ignition is turned on.
Option 3 — If you want the device to switch into low power mode when the
engine battery voltage drops below a certain value:
· Connect pin 3 to pin 1
· In ACEmanager, configure the Low Power Mode with a voltage level
threshold
The device operates normally until the battery voltage drops below the thresh-
old value, triggering the Low Power Mode. The device resumes normal opera-
tion when the battery voltage rises above the threshold value.
Option 4 — If you use a separate battery other than the engine’s for device
power (such as in an ambulance or other application that has a stand-alone
battery power system), but it isn't connected to an ignition or an on/off
switch, and you do not want the battery drained:
· Connect pin 3 to pin 1
· In ACEmanager, configure the Low Power Mode with a voltage level
threshold
The device operates normally until the battery voltage drops below the thres-
hold value, triggering the Low Power Mode. The device resumes normal oper-
ation when the battery voltage rises above the threshold value.