Dwyer CDTA - Manual

Series CDTA Communicating Carbon Dioxide Detector
Specifications - Quick Start Installation and Operating Instructions
Bulletin AQ-CDTA-QS
DWYER INSTRUMENTS, INC.
Phone: 219/879-8000 www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A. Fax: 219/872-9057 e-mail: [email protected]
SPECIFICATIONS
Sensor (CO
2
): Single-beam, dual-wavelength NDIR;
Humidity: Capacitive polymer;
Temperature: Solid state band gap.
Range:
CO
2
: 0 to 2000 or 5000 PPM CO2 (depending on model);
Humidity: 0 to 100% RH;
Temperature: 32 to 122°F (0 to 50°C).
Accuracy:
CO
2
: ±40 ppm ±3% of reading;
RH: ±2% (10 to 90% RH);
Temperature: ±1°C @ 25°C.
Temperature Dependence (CO
2
): ±8 ppm / °C at 1100 ppm.
Non-Linearity (CO
2
): 16 ppm.
Pressure Dependence (CO
2
): 0.13% of reading per mm of Hg.
Response Time (CO
2
): 2 minutes for 99% step change.
Temperature Limits: 32 to 122°F (0 to 50°C).
Humidity Limits: 10 to 95% RH (non-condensing).
Power Requirements: 10 to 42 VDC / 10 to 30 VAC.
Power Consumption:
Average: 0.5 watts;
Peak: 1.2 watts.
Output: 2-wire RS-485, Modbus ® RTU or BACnet MS/TP communication
protocol.
Weight: 4.4 oz (125 g).
Agency Approvals: BTL, CE, RoHS.
The Series CDTA Communicating Carbon Dioxide Detector combines the
function of three room sensors into a single, compact housing. Parameters include
carbon dioxide, humidity, temperature, and temperature set point with override. By
having field selectable Modbus
® and BACnet Communications, only four wires are
needed for power and the communication signal. The communicating detectors
can be daisy-chained together to further reduce installation cost. In order to reduce
the set up time, the RS-485 MAC address is set up using on board dip switches.
A second set of dip switches are used to select whether output is Modbus
® RTU or
BACnet MS/TP communication protocols and to limit access to the set up menu.
Like our Series CDT Carbon Dioxide Transmitter, the Series CDTA uses a Single
Beam Dual Wavelength Non-Dispersive Infrared (NDIR) sensor to measure the
carbon dioxide level. This technology can be used in installations that will be
occupied 24 hours per day. For improved accuracy, the transmitter can be field
calibrated to the environmental conditions of the installation. Also, the barometric
pressure can be programmed to correct for altitude. The humidity uses a capacitive
polymer sensor and the temperature is measured using a 10KΩ thermistor sensor.
The humidity sensor is field replaceable without the need for additional calibration.
Optional local and remote displays are available to display any of the parameters.
For applications in which the building occupants aren’t familiar with CO
2
concentrations, the LCD can be programmed to display temperature, humidity, or
temperature set point instead.
Installation
3.65
[92.72]
3.56
[90.42]
1.08
[27.33]
4.50
[114.30]
2.80
[71.12]
1.10
[27.96]
For optimal performance, self calibration feature of the
transmitter requires exposure to normal outdoor equivalent
carbon dioxide level once every thirty days.
NOTICE
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
European North American
Disconnect power supply before installation to prevent electrical
shock and equipment damage.
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.
CAUTION
Use electrostatic discharge precautions (e.g., use of wrist
straps) during installation and wiring to prevent equipment
damage.
NOTICE
Avoid locations where severe shock or vibration, excessive
moisture or corrosive fumes are present. NOTICE
Do not exceed ratings of this device, permanent damage not
covered by warranty may result. NOTICE
Modbus ® is a registered trademark of Schneider Automation, Inc.