Optional Outdoor Air Monitor; Thermal Dispersion Airflow Measurement Technology - Daikin DPS005 Installation And Maintenance Manual

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 65: Bead-in-Glass Thermistor
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
Figure 66: Bead-in-Glass Thermistor Probe
Zero Power Thermistor
Approaching
Airstream
Self-heated Thermistor
www.DaikinApplied.com
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
b . MicroTech III controller (M on the MCB or M on the
2 . Power Wires (24 VAC) to the outdoor air monitor
controller.
Thermistor aging
process ensures a . 24VAC from the unit control panel to the controller
long term stability
Outdoor air monitor controller settings
1 . Set Controller SW1 switch to Vdc.
2 . Set power switch to ON.
Waterproof potting
compound protects
Outdoor air monitor controller configuration/set up
assembly from the
environment
(see Appendix, Figure 87 on page 119
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 29: Settings by Cabinet Size
Heat transferred to
the airstream is
Model
proportional to the
airflow rate
003–006
007–015
016–028
69
o
pTIonal
EXP_D) to the controller's analog output terminal 1.
EXP_D) to the controller's analog output terminal
COM.
terminals L1 and L2.
Table 29)
Table 29)
Area sq .ft .
Unit Size
(AR1)
Small cabinet 2 .25
Medium cabinet 4 .5
Large Cabinet 10 .25
IM 1125-7 • REBEL ROOFTOPS
o a M
uTdoor Ir onITor
o o a M
pTIonal uTdoor Ir onITor
for navigating the
Full scale output CFM
(FS1)
2,400
6,000
11 .0