Facility Explorer FX15 - Connecting Active Sensors Powered by 24 VAC

FX15 Controller Technical Bulletin
35
Connecting Active Sensors Powered by 24 VAC
The FX15 can accept active temperature, pressure, flow, and humidity
sensors providing 0-10 V or current signals powered by 24 VAC.
A second transformer (24 VAC/24 VAC, 3 VA maximum) powering
only the Analog Input is required to maintain the insulation from the
microprocessor.
32 33 34 35
939291
FX
16
220
Vac
24 Vac
24 Vac
24 Vac
24V
V
~ Hot
V ~ Com
Earth
24V
1 2 3
AGND
AI1
EXT V
4 5
AGND
AI2
6
7
AGND
AI3
8
EXT V
Active Sensor powered at 24 V
Figure 35: Active Sensor powered at 24 VAC Connection Diagram
Table 6: Active Sensors Powered by 24 VAC
FX15 Terminals
Sensor Cable
Description
AGND (1)
Green
Common Reference
AI1 (2)
White
Signal Output
Note: The numbers inside the parentheses are the FX15 controller
terminal numbers.
IMPORTANT: Not powering the Analog Input with a second transformer, or
powering the AI with the power supply on another FX controller, results in a
short circuit causing the failure of the FX15 controller.
3 VA max
15 VA
FX15