Trane Performance Climate Changer PSCA, Инструкция по установке, эксплуатации и обслуживанию

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Start-Up
CLCH-SVX013B-EN 67
Airflow Measuring Systems
Traq™ Dampers
Traq dampers are low-leak dampers that modulate and
measure airflow. Each Traq damper section is supplied
with a factory-mounted ventilation control module (VCM)
on the interior of the mixing box section. The VCM has an
input terminal for power and an output terminal for air
velocity (see
Figure 84 ). A direct-digital controller controls
the factory-mounted and wired actuators.
Figure 84. Traq damper terminal connections
Ventilation Control Module
Velocity (2-10 Vdc)
GND
24 Vac
GND
J4 (Red)
J4 (White)
J2 (Black)
J2 (Green)
J5 (Yellow)
J5 (White)
Thermistor
Figure 85. Traq damper terminal connections
VCM (Transducer) Calibration.
The VCM has an auto-
zero function that recalibrates the transducer once every
minute. When troubleshooting, allow for the recalibration
time before making any measurements.
Input Power.
The only input the VCM needs is the 24 Vac
power connected to the J2 plug (green and black wires).
Output Velocity Signal.
The 2 to 10 Vdc linear output
signal from the VCM represents air velocity. This voltage
can be converted to represent airflow (cfm or L/s) using the
formula below and
Table 13 .
Airflow = k (cfm @ 10V)
volts 2
–
 
8
------------------------------
or
Airflow = k (L/s @ 10V)
volts 2
–
 
8
------------------------------
For example, if the VCM on a size 30 air handler at sea
level (k=1) has a 10-volt signal, it would represent
24,492 cfm (11,559 L/s) through the Traq damper. If
the voltage were 6 volts, airflow through the Traq
damper would be 12,246 cfm (5779 L/s).
Table 13. Altitude adjustment factors
Sea level = 1.0
Elevation (feet) k
1000 0.982
2000 0.964
3000 0.949
4000 0.930
5000 0.914
6000 0.897
7000 0.876
8000 0.860
9000 0.846
10,000 0.825
In Table 14 , the cfm at 10Vdc is a calculated value based on
area and peak velocity. In certain situations, it can be
advantageous to raise the velocity of air through the
remaining Traq dampers by closing off one or more
dampers in the unit. The cfm at 10Vdc can be recalculated
based on the proportion of remaining Traq dampers or by
multiplying the remaining area of dampers by peak
velocity. Calculations are based on VCM voltage versus
airflow at sea level.