Optional Outdoor Air Monitor; Technology - Daikin DPS 003 Manual

Optional Outdoor Air Monitor

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 43: 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 44: Bead-in-Glass Thermistor Probe
Zero Power Thermistor
Approaching
Airstream
Self-heated Thermistor
46
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
b. MicroTech III controller (M on the MCB or M on the
2. Power Wires (24 VAC) to the outdoor air monitor
Thermistor aging
process ensures
controller.
long term stability
a. 24VAC from the unit control panel to the controller
Outdoor air monitor controller settings
1. Set Controller SW1 switch to Vdc.
Waterproof potting
compound protects
2. Set power switch to ON.
assembly from the
environment
Outdoor air monitor controller configuration/set up
(see Appendix, Figure 61 on page 88
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
Heat transferred to
the airstream is
proportional to the
airflow rate
Table 25: Settings by Cabinet Size
Small cabinet
Large cabinet
on the 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 25)
Table 25)
Unit size Area sq .ft . (AR1)
2 .25
4 .5
for navigating the
Full scale output CFM
(FS1)
2,400
6,000
IM 1125-5