Optional Outdoor Air Monitor
www.DaikinApplied.com
85
IM 1125-13 • REBEL ROOFTOPS
Optional Outdoor Air Monitor
Thermal Dispersion Airflow Measurement Technology
Thermal dispersion technology relates the velocity of the air
to the power and rise in temperature of a heated element in a
moving airstream. A precise bead-in glass thermistor probes
the airflow rate and air temperature. Multiple sensing points are
used to produce an average velocity for true volumetric airflow
(CFM/LPS). Each individual sensor node is calibrated to NIST
traceable airflow standards at 16 points, resulting in a accuracy
of 2% of the reading.
Figure 88: Bead-in-Glass Thermistor
Figure 89: Bead-in-Glass Thermistor Probe
Connecting to MicroTech III Controllers
Wiring
1 .
Connect analog control wires from the MicroTech III
Controller to the outdoor air monitor controller.
a .
MicroTech III controller (X1 on the MCB or X11 on the
EXP_D) to the controller's analog output terminal 1.
b .
MicroTech III controller (M on the MCB or M on the
EXP_D) to the controller's analog output terminal
COM .
2 .
Power Wires (24 VAC) to the outdoor air monitor
controller.
a .
24VAC from the unit control panel to the controller
terminals L1 and L2.
Outdoor air monitor controller settings
1 .
Set Controller SW1 switch to Vdc.
2 .
Set power switch to ON.
Outdoor air monitor controller configuration/set up
Appendix, Figure 110 on page 146
Controller keypad)
1 .
Set LCD1 U/M to "CFM"
2 . Set AR1 (see
3 .
Set OUT1 U/M =CFM
4 .
Set OUT1 =0–10V
5 . Set FSI (see
)
Table 35: Settings by Cabinet Size
Model
Unit Size
Area sq .ft .
(AR1)
Full scale output CFM
(FS1)
003–006
Small cabinet
2 .25
2,400
007–015
Medium cabinet
4 .5
6,000
016–028
Large Cabinet
10.25
11.0
Thermistor material
designed for self-heat
applications is fused
to dumet wire leads
Dumet wire ensures
hermetically sealed
glass encapsulation
Kynar
®
coated wires are
welded to dumet leads
Thermistor aging
process ensures
long term stability
Waterproof potting
compound protects
assembly from the
environment
Zero Power Thermistor
Approaching
Airstream
Self-heated Thermistor
Heat transferred to
the airstream is
proportional to the
airflow rate
