12 • Chapter 3: Installation
AirLink 9850 Gas Monitor Operator’s Manual
Wiring the AirLink 9850
This section describes procedures for DC power source wiring, AC power source wiring, Modbus out
wiring, USB virtual COM port connection, Ethernet connection, 4-20 mA output wiring, and fault
indicator wiring.
The following wiring connections must be made before starting up the AirLink 9850.
CAUTION:
The internal components can be static sensitive. Use caution when opening the enclosure
and handling internal components.
WARNING: Make all connections to the AirLink 9850 before you plug in or turn on the AC or DC
power source. Before you make any wiring adjustments, always verify that all power
sources are not live.
Connecting a DC Power Source
NOTE:
The AirLink 9850 is configured for AC or DC operation, depending on how it is ordered. If
you are using AC power as the primary power source, go to the next section, “Connecting an
AC Power Source”.
Provide a clean and stable 12-35 VDC. Failure to do so may cause the unit to not operate properly.
Voltage spikes higher than 35 VDC may damage the unit.
1. Open the enclosure box to expose the Front Panel.
2. Unscrew the two thumb screws on the Front Panel.
3. Open the Front Panel so that the Terminal Board is exposed (back of Front Panel).
4. Locate the Power Terminal (on the lower right side of the Back Panel) and connect the + wire (red)
to the terminal marked “+12-35 VDC”.
5. Connect the - wire (black) to the terminal marked “GND”.