Greystone Energy Systems CD2DT Series User manual

Page 1
INTRODUCTION
The duct CO2device uses a highly accurate and reliable non-dispersive
infrared (NDIR) sensor in an attractive enclosure with a gasketed, hinged
cover for duct applications to monitor CO2levels. The sensor uses
dual channel optics and LTA (long term adjustment) signal processing
technology to deliver industry leading long term accuracy and reliability.
These technology features ensure optimum measurement stability for
both periodic and constant occupancy applications so the device is
equally suitable for return-air measurement from the classroom or the
hospital room.
Standard features include a eld selectable output signal of either 4-20 mA, 0-5 Vdc or 0-10 Vdc for the
highest versatility, programmable CO2measurement span, a backlit alpha-numeric LCD and easy menu
operation for conguration.
Optional features include a resistive temperature sensor output (with LCD display of temperature in
either °C or °F), a control relay with programmable setpoint, hysteresis and time delay, and either a
conduit or cable gland connection point.
BEFORE INSTALLATION
Read these instructions carefully before installing and commissioning the device. Failure to follow these
instructions may result in product damage. Do not use in an explosive or hazardous environment, with
combustible or ammable gases, as a safety or emergency stop device or in any other application where
failure of the product could result in personal injury. Take electrostatic discharge precautions during
installation. De-energize the power supply prior to installation, this device is intended for indoor air
conditioned spaces, contact factory or other applications. Do not exceed device ratings. This product
is not intended for life-safety applications.
NOTE: This CO2sensor incorporates a Self Calibration feature to correct CO2sensor drift. This feature is
recommended for applications where the CO2will be exposed to fresh air (400 ppm) at least one hour
per day. If the monitored space is occupied 24 hours or consistently maintains higher or lower levels
of CO2, it is recommended that this feature be turned o, but yearly calibration will be required. If the
self calibration is disabled at installation time without allowing for 7 day auto calibration cycle, then a
manual calibration should be performed to ensure accuracy of the device.
MOUNTING
The duct type sensor installs on the outside of a return air duct with the sampling tube inserted into the
duct. Use the included foam plug to prevent air from entering the enclosure through the conduit and
causing an incorrect reading.
Mount the sensor in an easily accessible location in a straight section
of duct at least ve feet from corners or other items that may cause
disturbances in the air ow. Avoid areas where the detector is exposed
to vibrations or rapid temperature changes.
The duct CO2detector principal of operation is based on the Venturi
eect of the probe that extends into the HVAC duct. Air owing through
the duct is forced into the vent holes on one side of the probe, into
the enclosure, over the CO2sensor and then is drawn back out of the
enclosure via the probe vent holes on the opposite side.
NOTE: To ensure proper temperature readings, if present, the
temperature inlet on the probe must be installed directly into the
airow. See Figure 1.
EMT Connector
Thread adapter and
cable gland tting
Figure 1 Airow
Figure 3
Figure 2
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Duct Carbon Dioxide Transmitter
CD2DT Series - Installation Instructions

Page 2
Drill or punch a 7/8” or 1” hole in the duct at the preferred location and
insert the probe into the hole to mark the enclosure mounting holes.
Remove the unit and drill the two mounting holes.
Clean all drilled holes of debris before mounting the device. Mount
the enclosure to the duct with two sheet metal screws such that the
duct air ow is parallel with the vent holes in the probe (i.e.: air ows
directly into the probe holes). To prevent air leaks, ensure the gasket is
compressed around the probe between the device enclosure and the
air duct. See Figure 1.
The enclosure has a hinged cover with a latch. Open the cover by pulling slightly on the latch on the
bottom of the enclosure, at the same time pulling on the cover. See Figure 2. A 1/2" NPT threaded
connection hole is provided in the side of the enclosure. Screw an EMT connector or cable gland
connector in until tight. A weatherproof conduit or cable gland tting is recommended. There is an
optional 1/2" NPT to M16 thread adapter and cable gland tting. See Figure 3.
Two security screws are provided which can be installed to help secure the cover once settings and wiring
connections are complete. See Figure 4.
WIRING
Deactivate the power supply until all connections are made to the device to prevent electrical shock
or equipment damage. Use 16-22 AWG shielded wire for all connections (only ground the shield at the
controller end) and do not locate the device wires in the same conduit with wiring used to supply inductive
loads such as motors. Pull at least six inches of wire into the enclosure and complete the wiring connection
according to the wiring diagram. See Figure 5.
This is a 3-wire sourcing device. Connect the plus DC or the AC voltage hot side to the PWR terminal
and the common is connected to the COM terminal. The device
is reverse voltage protected and will not operate if connected
backwards. It has a half-wave power supply so the supply
common is the same as the signal common. Several devices
may be connected to one power supply and the output signals
all share the same common. Use caution when grounding the
secondary of a transformer or when wiring multiple devices
to ensure the ground point is the same on all devices and the
controller. See Figure 6.
The CO2analog output is available on the CO2terminal. This
signal is switch selectable for either 4-20 mA or voltage output
(0-5 / 0-10 Vdc) and connects to the controller analog input. See
Figure 7.
Check the controller Analog Input to determine the proper connection before applying power. Both
current and voltage signals are referenced to the COM terminal. The current output operates in the active
mode and does not require a loop power supply (the signal current is generated by the transmitter and
must not be connected to a powered input or device damage will result).
Figure 5
Figure 7 Figure 8 Figure 9
Figure 6
Power Supply
Wiring for CO2output signal and
24 Vdc power from controller
Wiring for all output and external 24 Vac power
transformer or external 24 Vac power supply
CO2
COM
PWR
RELAY TEMP
CO2
COM
PWR
Analog Input
COMMON
+24 Vdc
COMMON
Digital Input
Analog Input
COMMON
Analog Input
COMMON
COMMON
24 Vac
Controller
Alarm Controller
24 Vac Transformer /
Power Supply
mA
VOLT
Current
4-20 mA
Voltage
0-5 or 0-10 Vdc
VOLT
mA
Figure 4
PWR
COM
CO2
TEMP
UP
DOWN
MENU
RELAY
VOLT
mA
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Page 3
OUTPUT SCALING
The CO2output signal is scaled such that 4-20 mA (or 0-5 / 0-10 Vdc) equals 0-2000 ppm by default. The
signal span may be changed via the Setup Menu from 1000 to 10,000 ppm in 500 ppm increments.
STARTUP MODE
Verify the device is properly wired and connections are tight. Ensure the mA / VOLT switch is set for the
correct signal type. Apply power and the LCD will indicate the software version number, the output signal
type and then the sensor will begin a one minute warm-up countdown. When the warm-up time expires
the device will enter normal mode.
NORMAL MODE
The sensor will begin reading the CO2level (and temperature if it is installed), output the correct analog
signal and display the values on the LCD. If the relay is installed, the measurements will be compared to
the setpoint and appropriate action taken. The keypad is monitored and if the <MENU> key is pressed the
device will enter the Setup Menu. The Setup Menu can be accessed to congure the device for required
operation.
RELAY MODE
The optional relay can be used as an alarm signal to indicate that a setpoint has been exceeded. For
the basic CO2product, the relay may be congured via the Setup Menu as a high or low alarm and the
setpoint value, hysteresis and on-delay time may be set. The relay will activate and close the contacts if
the CO2measurement goes above the setpoint (for a high alarm) or below the setpoint (for a low alarm).
If required, this action can be delayed by a time period (relay delay time) to prevent false alarms. After the
relay is activated, the measurement must fall below the setpoint - hysteresis value (for a high alarm) or go
above the setpoint + hysteresis value (for a low alarm) to deactivate the relay and open the contacts. The
high/low assignment, setpoint, delay time and hysteresis values may all be programmed via the Setup
Menu as required.
If the optional temperature sensor is installed, the relay operation may be assigned to operate as a
temperature high or low alarm instead of a CO2alarm. All the same relay parameters may be congured
to set up the alarm as required.
SETUP MENU
The device has several parameters that can be congured locally via the Setup menu using the keypad
and LCD. Any changes made are saved in non-volatile memory and are restored in case of a power loss. The
menu can be accessed at any time after the start-up mode and if there is 5 minutes of inactivity the menu
will close and normal operation will continue.
To enter the menu, press and release the <MENU> key. This will enter the Setup Menu step 1, pressing the
<MENU> key a second time saves the setting and advances to step 2. Each press of the <MENU> key saves
the current setting and advances the menu item. The <UP> and <DOWN> keys are used to make changes
to program variables by scrolling through the available options. The rst column below shows what will
be displayed on the LCD, including the default value.
<MENU> Press and release the <MENU> key to enter the Setup Menu
CO2 Span
2000 ppm
Self-Cal
ON
The CO2Span value controls the analog output scaling. CO2span can be changed
from 1000 to 10,000 ppm in 500 ppm increments using <UP> or <DOWN>. If CO2
Span = 2000 ppm, then the output signal is scaled 0-2000 ppm = 4-20 mA. Factory
default is 2000 ppm.
The Self-Cal feature <MENU> when enabled requires the sensor to be exposed
to fresh air for at least one hour every twenty-four hours. When rst installed the
sensor requires a minimum of seven days of operation with fresh air exposer daily
to allow the algorithm to adjust for self-calibration. Default for device is having this
feature disabled enabled “ON". If disabling this feature a manual calibration should
be performed to ensure accuracy of the device.
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
1. SPAN
2. SELFCALIBRATION
The optional relay output connects to the RELAY terminals. The relay output is completely isolated and
has a Normally Open (NO) signal. This signal can be used to directly control an alarm or ventilation fan. See
specications for contact ratings. See Figure 8.
The optional two-wire temperature sensor output is available with various RTDs and thermistors to suit all
control applications and is available on the TEMP terminals. See Figure 9.
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IN-GE-CD2DTXXX-03

Page 4
Altitude
0 m
The Altitude value allows CO2compensation for local atmospheric pressure and
altitude and ensures the highest CO2accuracy. Altitude can be changed from 0 to
2550 meters in 50 meter steps using <UP> or <DOWN>. It will take a few moments
to change the setting, then the menu will advance to the next step. Factory default
is 0 m (sea level).
<MENU> Press to advance to next menu item
3. ALTITUDE
V Output
0-5 Vdc
The V Output value controls the analog output voltage span if the PCB switch is set
to VOLT. V Output can be set to either 0-5 Vdc or 0-10 Vdc using <UP> or <DOWN>.
This setting has no eect if the PCB switch is set to mA. Factory default is 0-5 Vdc.
<MENU> Press to advance to next menu item
4. OUTPUT VOLTAGE SPAN
Output
Direct
The Output value controls the analog output signal direction. Use <UP> or
<DOWN> to change the setting from Direct (4-20 mA, 0-5 Vdc or 0-10 Vdc) to
Reverse (20-4 mA, 5-0 Vdc or 10-0 Vdc) if reverse action is required. Factory
default is Direct.
<MENU> Press to advance to next menu item
5. OUTPUT SIGNAL DIRECTION
Output
Test OFF
The Output Test value controls the analog output signal for testing purposes.
Use <UP> or <DOWN> to toggle the output signal to OFF (normal operation),
MIN (minimum output) or MAX (maximum output). The actual output signal will
depend on the PCB switch position (mA or VOLT) and the V Output setting (for
voltage operation). Press <MENU> to set it back to OFF and advance. Factory
default is OFF.
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
6. OUTPUT TEST
Temp
Units °C
Display
CO2 ppm
CO2
1235 ppm
Temp
24.3 °C
1235 ppm
24.3 °C
CO2
1235 ppm
Temp
24.3 °C
The Temp Units setting is used to select °C or °F display of temperature. Use
<UP> or <DOWN> to select. The selection will also control available setpoint
ranges if the setpoint option is installed. Factory default is °C.
Display is used to control what information is displayed on the LCD. The
selections depend on the installed options. Use <UP> or <DOWN> to select
either CO2ppm, Temp, CO2+Temp, Rotate or None. Factory default is CO2ppm.
For a basic CO2only device, the selection is limited to CO2ppm or None.
CO2ppm Only the actual ppm value of
the CO2reading will be displayed
Temp Only temperature is displayed
(°C or °F depends on units setting)
CO2& Temp CO2ppm and temperature both
displayed at the same time
Rotate All available sensor readings rotate
at 2 second intervals
None No measurement information is displayed in
normal mode, the menu will still display in
Setup Menu mode
7. TEMPERATURE UNITS
8. DISPLAY
Only if Temperature Sensor option Installed
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Page 5
BackLite
Auto
The BackLite setting is used to control how the LCD backlight functions. Use
<UP> or <DOWN> to select either Auto, O or On. Auto means the backlight only
lights when a menu is accessed or when the setpoint is activated (ie: when a key
is pressed), O means the backlight is always o and On means it is always on.
Factory default is Auto.
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
9. BACKLIGHT
Only if Relay option Installed
Only if Temperature Sensor option Installed
Relay
CO2
T Oset
0.0 °C
The Relay setting allows the relay alarm to be assigned to either CO2High,
CO2Low, Temp Hi or Temp Low as applicable. Use <UP> or <DOWN> to select.
Factory default is CO2High. If the temperature sensor is not installed then the
options will not be available.
The T Oset value allows calibration of the temperature value displayed on the
LCD. Units (°C/°F) follow the Temp Units setting. Use <UP> or <DOWN> to add
or subtract an oset from the temperature value. The range is -5.0 to 5.0 °C or
-9.0 to 9.0 °F in 0.1° increments. Factory default is 0.0 °C.
11. RELAY
10. TEMPERATURE OFFSET
Relay SP
1000 ppm
Relay SP
1000 ppm
The relay setpoint depends on the relay assignment set previously. Use <UP>
or <DOWN> to change the setting within the limits as shown in the table.
Note that only the one previous selection will be available. Note that a high
alarm activates when the measurement exceeds the setpoint and a low alarm
activates when the measurement goes below the setpoint. Use <MENU> to
save and advance.
or
12. RELAY SETPOINT
RELAY ASSIGNMENT DEFAULT SETPOINT SETPOINT RANGE RESOLUTION
Temp High 26.0°C / 79.0°F 5.0 to 40.0°C / 40.0 to 100.0°F 0.5°
Temp Low 15.0°C / 59.0°F 5.0 to 40.0°C / 40.0 to 100.0°F 0.5°
CO2High 1000 ppm 500 to 9000 ppm 100 ppm
CO2Low 1000 ppm 500 to 9000 ppm 100 ppm
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
Relay Hy
50 ppm
Relay Hy
0.5 °C
The Relay Hysteresis will depend on how the relay is assigned. Units will either
be in ppm for CO2or °C/°F for temperature.
Use <UP> or <DOWN> to change the Relay Hysteresis within the limits as
shown in the table.
Note that a high alarm resets when the measurement goes below (setpoint
- hysteresis) and a low alarm resets when the measurement goes above
(setpoint + hysteresis). Note the value is somewhat dependent on the setpoint
(ie: if the CO2setpoint is 500 ppm then the hysteresis cannot be 500 ppm).
or
13. RELAY HYSTERESIS
RELAY ASSIGNMENT DEFAULT SETPOINT SETPOINT RANGE RESOLUTION
Temp High or Low 0.5°C/F 0.2 to 5.0°C/F 0.1°C/F
CO2High or Low 50 ppm 25 to 500 ppm 25 ppm
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Page 6
Only if Relay option Installed
Relay
Dly 0min
Relay
Test OFF
Use <UP> or <DOWN> to change the Relay Delay time within the limits. The
delay time may be set from 0 to 9 minutes in 1 minute increments to prevent
false alarms. The default is 0 minutes (no delay).
Use <UP> or <DOWN> to toggle the relay ON or OFF to test the relay
operation. Press <MENU> to reset to OFF and advance.
14. RELAY DELAY
15. RELAY TEST
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
<MENU> Press to advance to next menu item
Calibrat
1000 ppm
Cal Ref
1000 ppm
This item is used to calibrate the CO2sensor by applying 1000 ppm CO2calibration
gas directly to the sensor. Consult the calibration instructions for the detailed
procedure.
After applying the gas for several minutes, hold either the <UP> or <DOWN>
key for 5 seconds to start the gas calibration. The display will blink during the
calibration time (approximately 10 seconds).
The display will change to “Calibrat / Done” when the calibration is complete. The
display may indicate “Calibrat / Fail” if the calibration fails.
The calibration reference screen allows user to set the calibration gas level used
for calibrating the sensor. Use <UP> and <DOWN> to adjust the ppm value of
calibration gas. The minimum value is 400ppm, the maximum value is 2000ppm.
Increment value is 50ppm for each step. Press <MENU> to save and advance. If no
calibration gas is available exposing the sensor to fresh outside can be used and
calibrate with 400PPM value. Another method is to determine the CO2 ambient
level using a calibrated unit as a reference and adjust calibration setting to desired
value
<MENU> Press to advance to exit the Setup Menu and return to normal mode
17. CALIBRATE
16. CALIBRATE
CALIBRATION
Calibration with gas requires a eld calibration kit with pressure regulator, tubing, sensor adapter and
bottle of CO2gas. The certied calibration gas is applied directly to the CO2sensor to perform a gas
calibration.
Ensure the regulator knob is turned o and then hand tighten the regulator to the CO2gas bottle. A
length of tubing should be connected between the regulator output and the sensor adapter hood.
Remove the cover of the device to be calibrated to expose the gas sensor. Carefully install the sensor
adapter hood over the CO2sensor on the PCB. The adapter should t snuggly and securely over the
sensor and remain in place during the entire calibration cycle. This will ensure a stabile ppm CO2
environment during calibration. Turn the regulator knob on to allow gas to ow to the sensor. The CO2
reading on the LCD will begin to approach ppm level of calibration gas . Wait 3 to 5 minutes until the CO2
reading stabilizes.
Enter the Setup Menu and use the <MENU> key to advance to the“Calibrat” item. Press and hold either
the <UP> or <DOWN> key for 5 seconds to start the gas calibration. The LCD will indicate “Calibrat
/ Done” if the process was successful. If “Calibrat / Fail” is displayed then the process may have to be
repeated. Press the <MENU> key to return to normal operation, shut o the gas supply and remove the
sensor adapter.
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IN-GE-CD2DTXXX-03

PRINTED IN CANADA
Page 7
SPECIFICATIONS
Gas Type Detected.................................................Carbon dioxide (CO2)
Sensor Type ..............................................................Dual channel non-dispersive infrared (NDIR)
Sensor Accuracy......................................................±(30 ppm + 3% of measured value)
Measurement Range.............................................0-2000 ppm (default), adjustable 1000-10,000 ppm
Pressure Dependency...........................................< ±2.5ppm/°C
Response Time ........................................................20 seconds (T63)
Warm-Up Time.........................................................1 minute
Sensor Life Span......................................................>15 years
Transmitter Accuracy ............................................±0.25% of span
(including linearity, hysteresis and repeatability)
Power Supply...........................................................24 Vdc ±20% or 24 Vac ±10%
(non-isolated half-wave rectied)
Protection Circuitry................................................Reverse voltage and transient protected
Input Voltage Eect...............................................Negligible over specied operating range
Output Signal Type ................................................4-20 mA (3-wire), 0-5 or 0-10 Vdc (eld selectable)
Current Consumption...........................................Current: 75 mA @ 24 Vdc max, 150 mA @ 24 Vac max
Voltage: 50 mA @ 24 Vdc max, 100 mA @ 24 Vac max
Output Drive @ 24 Vdc .........................................Current: 550Ω max
Voltage: 10,000Ω min
Ambient Operating Range..................................0 to 50°C (32 to 122°F), 0 to 95 %RH non-condensing
Storage Conditions................................................-40 to 70°C (-40 to 158°F), 0 to 95 %RH non-condensing
LCD Display Units ...................................................ppm (CO2), °C/°F for optional temperature/setpoint
Display Range..........................................................0-10,000 ppm, 0 to 50°C / 0 to 122°F
Display Size...............................................................35mm W x 15mm H (1.4" x 0.6")
Digit Height..............................................................2-line x 8 character
OPTIONAL TEMPERATURE SENSOR
Type.............................................................................Thermistor or RTD
Accuracy ....................................................................Thermistors: ±0.2°C (±0.36°F) @ 25°C (77°F)
Platinum RTD's: ±0.3°C (±0.54°F) @ 0°C (32°F)
Nickel RTD's: ±0.4°C (±0.72°F) @ 0°C (32°F)
Output........................................................................2-wire resistive
Relay (Optional 2-wire output)..........................Form A (N.O.), 2 Amps @ 140 Vac / 30 Vdc
Enclosure...................................................................Polycarbonate UL94-V0 (NEMA 4X)
116mm W x 100mm H x 54mm D (4.6" x 3.9" x 2.1")
Wiring .........................................................................Screw terminal block (14 - 22 AWG)
Approvals ..................................................................CE
Country of Origin.......................................................Canada
DIMENSIONS
112.5 mm
4.43"
53.7 mm
2.11"
152 mm
6"
22.5 mm
0.88"
116.5 mm
4.58"
99.7 mm
3.93"
0.5" NPT
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