Series CDTV Duct Mount Carbon Dioxide / Volatile
Organic Compound Transmitter
Specifications - Installation and Operating Instructions
Bulletin AQ-CDTV-D
The
Series CDTV
Carbon Dioxide / Volatile Organic Compound (VOC) Transmitter
reduces energy cost in buildings by lowering the amount of conditioned air based on
the occupancy of the space. By detecting both CO
2
and VOC, the transmitter can
also detect fumes that may need to be exhausted during lower occupancy periods.
Combining both measurements in one transmitter reduces both labor and material
costs by only having to install one CDTV-VOC unit, instead of separate CO
2
and VOC
transmitters.
Carbon dioxide measurements are taken using our proven Single-Beam Dual-
Wavelength Non-Dispersive Infrared (NDIR) sensor. Our sensor allows users to get
accurate measurements without waiting for the settling / correction periods of other
logic based sensors. Transmitters can be used in buildings and applications that have
24 hour occupancy and can be calibrated on site to match environmental conditions
for improved accuracy.
The VOC measurement is a single value derived from the presence of substances
including alcohols, aldehydes, aliphatic hydrocarbons, amines, aromatic hydrocarbons,
CO, CH4, LPG, ketones, and organic acids. Although a standard unit of measure is
not currently defined, the VOC measurement unit “ppm CO
2
equivalent” used by the
device is commonly used in the industry. The VOC measurement does not actually
measure CO
2
, but instead senses and indicates an air quality value that approximately
correlates perceived comfort levels to similar concentrations of CO
2
in the environment.
Single-beam dual-wavelength sensor advantages:
• Automatically corrects for aging effects in occupied and unoccupied buildings
• Perfect for hospitals and manufacturing plants that are occupied 24 hours per
day
• Measures actual unfiltered light intensity directly
• Eliminates error from incorrect assumptions of gas concentration in theoretical
logic assumption methods
SPECIFICATIONS
Range:
CO
2
: 0 to 2000 or 0 to 5000 ppm (depending on model); VOC: 0 to 2000
ppm CO
2
equivalent.
Accuracy:
CO
2
: ±40 ppm +3% of reading.
Temperature Dependence:
±8 ppm / °C at 1100 ppm.
Non-Linearity:
CO
2
: 16 ppm.
Pressure Dependence:
CO2: 0.13% of reading per mm of Hg.
Response Time:
CO
2
: 2 minutes for 99% step change; VOC: 5 minutes.
Temperature Limits:
32 to 122°F (0 to 50°C).
Power Requirements:
16 to 35 VDC / 19 to 28 VAC.
Power Consumption:
Average: 2 watts; Peak: 3.75 watts.
Sensor:
CO
2
: Single-beam, dual-wavelength NDIR; VOC: MEMS (metal oxide
semiconductor).
Output:
Current: 0 to 20 mA, 4 to 20 mA, 0 to 10 mA, or 2 to 10 mA (depending on
selection jumper, max 500 Ω); Voltage: 0 to 10 VDC, 2 to 10 VDC, 0 to 5 VDC, or 1
to 5 VDC (depending on selection jumper, min 500 Ω); Relay: SPST NO 2A @ 30
VDC.
Weight:
5.6 oz (158.8 g).
Agency Approvals:
CE.
INSTALLATION
Make sure all connections are in accordance with the job wiring diagram and in
accordance with national and local electrical codes. Use copper conductors only.
LEED
®
is a registered trademark of the U.S. Green Building Council.
Disconnect power supply before installation to prevent electrical
shock and equipment damage.
WARNING
Upon powering the transmitter, the firmware version will flash on
the display. A warm up period of 30 minutes is required for the
transmitter to adjust to the current CO
2
concentration.
NOTICE
Self calibration feature of the transmitter requires exposure to
normal outdoor equivalent carbon dioxide level once every thirty
days.
NOTICE
Use electrostatic discharge precautions (e.g., use of wrist straps)
during installation and wiring to prevent equipment damage.
CAUTION
Avoid locations where severe shock or vibration, excessive
moisture or corrosive fumes are present.
CAUTION
Do not exceed ratings of this device. Permanent damage not
covered by warranty may result.
CAUTION
1/8˝
[3.17]
4-25/32˝
[121.44]
4-9/32˝
[108.74]
2-13/16˝
[71.44]
Ø3-5/16˝
[84.14]
11-49/64˝
[298.85]
Ø1-15/64˝
[31.35]
®
DWYER INSTRUMENTS, INC.
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A.
Phone: 219/879-8000
Fax: 219/872-9057
www.dwyer-inst.com
e-mail: [email protected]
