Trane CSAA User Manual

Start-Up
CLCH-SVX07K-EN 133
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 42.
In Table 43 through Figure 50, 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. Setup details are available on
the HUB - DOC-106531.
Figure 167. Traq damper terminal connections
Airflow = k (cfm @ 10V)
or
Airflow = k (L/s @ 10V)
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 42. 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
volts 2–
8
------------------------------
volts 2–
8
------------------------------
Table 43. Back or top inlet standard Traq damper-air mixing and indoor economizer section
Unit Size Part Number
Traq Damper
Size (inches)
Quantity
Peak Velocity
(fpm)
Total Area
(ft
2
)
CFM @ 10VDC
Peak Velocity
L/s @ 10VDC
Peak Velocity
3 495100860001 13 1 2475 0.92 2279 1076
4, 6 495100860001 13 2 2475 1.84 4559 2151
8, 10 495100860001 13 3 2475 2.76 6838 3227
12, 14, 17 495100870001 16 3 2475 4.19 10,365 4891
21, 25 495100890001 20 3 2600 6.54 17,012 8028
30, 35, 40 495100880001 24 3 2600 9.42 24,492 11,558
50, 57 495100900001 28 3 2600 12.83 33,358 15,742
66 495100900001 28 4 2600 17.10 44,460 20,981
80 495100900001 28 5 2600 21.38 55,588 26,232
100, 120 495100900001 28 6 2600 25.66 66,716 31,483

Trane CSAA Specifications

General

Brand	Trane
Model	CSAA
Category	Air Handlers
Language	English