Sierra Wireless AirLink GX450 Hardware User's Manual page 35

Pin 4 (General Purpose I/O)
This pin is a digital input/output (green wire on DC cable).
Pin 4 either:
•
•
It has a maximum rating of 30 V and 50 mA sink current. The pin is user programmed. For
information on configuring Pin 4 (Digital Input/Relay Output 1 in ACEmanager) refer to the
ALEOS Software Configuration User Guide.
One way to use pin 4 is with events reporting. In ACEmanager you:
1. Create an Event.
2. Specify an Action.
There are several typical uses for Pin 4:
•
•
Rev. 11 July 2019
Monitors digital inputs and outputs
Drives a relay
This triggers the gateway to act when it sees a specific input. For example, you can tell
the gateway to do something when the Pin 4 state (Digital Input/Relay Output 1 in
ACEmanager) changes. This could be when a door is opened, activating a switch
attached to it.
These are instructions the gateway performs when it sees an event. For example, an
email could be sent to security, saying the door is open, giving the time, location and
other information.
As a digital input, it monitors a switch, using its opening or closing to record events or
monitoring external voltages of up to 30 VDC. For example, you could use it to
measure the voltage on a 24 VDC light bulb and have the gateway react when it turns
on.
When the switch, or input voltage is:
· Open (2.2 VDC to 30 VDC) – It is read as a digital input =1
· Closed (0 to 1.2 VDC) – It is read as a digital input =0
AirLink GX gateway
51 k
internal
pull up
I/O Circuit
Examples: Door opening/closing, valve opening/closing, ignition on/off, tow bar up/down,
empty/full container.
Figure 2-21: Digital Input Operation
As a digital output, it can trigger an alarm, siren, door lock or open a valve or a switch.
Pin 4 is an open collector transistor output normally at 3.3 VDC. When triggered, it is
pulled to low.
3.3 V
Contact
35
Installation and Startup
Contact closed
Digital 0
0 VDC to 1.2 VDC
Contact open
Digital 1
2.2 VDC to 30 VDC
Ground
4114008