BAPI CO2 Duct Manual

Building Automation Products, Inc., 750 North Royal Avenue, Gays Mills, WI 54631 USA
Tel:[phone] • Fax[phone] • E-mail:[email protected] • Web:www.bapihvac.com
Specications subject to change without notice.
1 of 4
Installation & Operating Instructions
rev. 08/21/1728173_ins_CO2_Duct
CO2 Duct and Rough Service Sensor
The BAPI CO2 Duct Sensor is an accurate and reliable way
of incorporating demand controlled ventilation. It measures
CO2 in ranges of 0 to 2,000, 0 to 5,000, 0 to 10,000 and 0
to 50,000 ppm with a eld selectable output of 0 to 5 or 0 to
10 VDC.
The Single Beam (ACD) unit has been optimized for
periodically unoccupied areas and features automatic
background calibration over a long time period to reduce
drift. The Dual Channel (DCD) “24/7” unit has been
optimized for continuously occupied areas and features a
3-point calibration process.
Barometric pressure changes from altitude or weather
can affect CO2 sensors, even putting them outside of their
specied accuracy. The BAPI unit has a built-in Barometric
pressure sensor that continuously compensates the output
for accurate readings despite the weather or altitude.
The Duct unit samples duct air using an aspiration tube.
The Rough Service unit features a ventilated BAPI-Box and
is ideal for areas such as outdoor air plenums, equipment
rooms, attics, green houses and warehouses. Optional
indication of the CO2 level as “Good, Fair or Poor” is
available as a 3-color LED for 0 to 2,000 ppm range units.
Identication and Overview
Fig. 1: Duct CO2 Sensor
Three-color
LED Fig. 2: Rough Service CO2 Sensor
Specications
Power:
12 to 24 VDC, 240mA
18 to 24 VAC, 12 VA Peak
CO2 Sensing Elements:
Single Beam Non-Dispersive Infrared (NDIR)
or Dual Channel NDIR for “24/7” Model
Selectable Output:
0 to 5 VDC or 0 to 10 VDC
Termination: 3 Terminals, 16 to 22 AWG
Wiring: 2 Pair
Operating Environment:
32 to 122°F (0 to 50°C)
0 to 95%RH non-condensing
Enclosure Material:
Polycarbonate, UL94 V-O
CO2 Detection Range:
0 to 2,000, 0 to 5,000, 0 to 10,000 and 0 to 50,000 ppm
Start-Up Time: 10 Minutes
Response Time:
Less Than 5 Minutes (after Start-Up Time)
CO2 Accuracy:
(Automatic Background Calib. Single Channel Model)
400 to 1,250 ppm: ±30ppm or 3% of reading,
whichever is greater
1,250 to 2,000 ppm: ±5% of reading + 30ppm
CO2 Accuracy:
(“24/7” Dual Channel Model)
75ppm or 10% of reading (whichever is greater)
CO2 Drift Stability (DCD “24/7” Units):
<5% of full scale over life of product.
Optional 3-Color LED (0 to 2,000 ppm range only):
Good, Green < 1,000 PPM CO2
Fair, Orange = 1,000 to 1,500 PPM CO2
Poor, Red > 1,500 PPM CO2
Certications: RoHS
Warranty Period:
5 Years from manufacture date

Building Automation Products, Inc., 750 North Royal Avenue, Gays Mills, WI 54631 USA
Tel:[phone] • Fax[phone] • E-mail:[email protected] • Web:www.bapihvac.com
Specications subject to change without notice.
2 of 4
Installation & Operating Instructions
rev. 08/21/1728173_ins_CO2_Duct
CO2 Duct and Rough Service Sensor
Duct Unit Mounting
1. BAPI recommends placing the sensor in the middle of the duct wall,
away from stratied air, to achieve the best reading. The unit should
also be a minimum of 3 duct diameters from an elbow, damper or
other duct restriction.
2. Drill a 1” hole for the aspiration probe.
3. Position the box so that airow is directly into the holes on one side
of the aspiration probe. There are no upstream or downstream holes,
the air direction is not important.
4. Mount the enclosure to the duct using BAPI recommended #10
screws through a minimum of two of the mounting feet on opposite
corners. A 1/8’ pilot screw hole in the duct makes mounting easier.
Use the enclosure mounting feet to mark the pilot-hole locations.
5. Snug up the screws so that the foam backing is depressed to prevent
air leakage but do not over-tighten or strip the screw threads.
6. Use the provided #6 screws to secure the cover for IP66 rating.
7. BAPI recommends sealing the conduit opening with berglass
insulation. Fig. 5: Duct unit mounting
Rough Service Unit Mounting
Mount the Rough Service sensor on a solid, non-vibrating surface. Wall mounting in a room should be 3 to 5 feet
above oor level. The Rough Service CO2 transmitter may be mounted in any orientation. If you are mounting
inside a duct or mixing box, mount with the latch facing into the moving air.
Refer to local codes for further sensor/transmitter installation information. See BAPI’s “Coverage Area” Application
Note for further mounting recommendations. To get to this application note, go to www.bapihvac.com, select
“Resource Library” from the banner. Click on “Application Notes” then scroll down the page to the heading “Air
Quality Related” and chose “Coverage Area and Mounting Recommendations for BAPI Indoor Air Quality Sensors”.
1. BAPI recommends #10 (M5) screws of a type and length suitable for the mounting surface. Four mounting
screws keeps the box from twisting,
twisting may prevent the latch from
operating properly. A pilot-hole
makes mounting easier. Use the
enclosure mounting feet to mark the
pilot-hole locations.
2. Snug up the screws so that the
foam backing is depressed but do
not over-tighten or strip the screw
threads.
3. Place the provided #6 screws into
the holes on each site of the lid
latch to make the cover tamper
resistant.
Fig. 3: Mounting the Rough Service
sensor to a wall
Fig. 4: Drill Template,
center 7/8” hole for rear
conduit entry

Building Automation Products, Inc., 750 North Royal Avenue, Gays Mills, WI 54631 USA
Tel:[phone] • Fax[phone] • E-mail:[email protected] • Web:www.bapihvac.com
Specications subject to change without notice.
3 of 4
Installation & Operating Instructions
rev. 08/21/1728173_ins_CO2_Duct
CO2 Duct and Rough Service Sensor
Termination
BAPI recommends using twisted pair of at least 22AWG and sealant lled connectors for all wire connections. Larger
gauge wire may be required for long runs. All wiring must comply with the National Electric Code (NEC) and local
codes. Do NOT run this device’s wiring in the same conduit as AC power wiring. BAPI’s tests show that uctuating
and inaccurate signal levels are possible when AC power wiring is present in the same conduit as the signal lines.
The CO2 outputs may
be eld congured for
0 to 5 VDC or 0 to 10
VDC outputs at any
time. Set the jumpers
on J3 as shown in
Figures 7 and 8. Fig. 7: J3 set for 0
to 10 VDC output
Fig. 8: J3 set for 0
to 5 VDC output
Terminal Function
PWR ............... 12 to 24 VDC, 240mA
18 to 24 VAC, 12 VA Peak
GND ................ To controller Ground [GND or Common]
OUT ................ Voltage Output, CO2 Signal
0 to 5 or 0 to 10 VDC, Referenced to GND
Note: Unit is not ready for operation until the 10 minute start-up time has elapsed.
Note: For proper operation, the
jumper on calibration connector J2
must be connected to one leg.
Fig. 6: Circuit Board
BAPI recommends wiring the product with power disconnected. Proper supply voltage, polarity, and
wiring connections are important to a successful installation. Not observing these recommendations may
damage the product and will void the warranty.
VC350A or VC350A-EZ
Voltage Converter
(VC350A shown below)
CO2 Sensor
POWERING WITH A BAPI VC350A
VOLTAGE CONVERTER
The CO2 unit requires 240mA of current
to operate correctly. If this is more
current than can be provided by the
controller power output, then the unit
can be powered by a BAPI VC350A or
VC350A-EZ Voltage Converter. Fig. 9: Powering with
a BAPI VC350A

Building Automation Products, Inc., 750 North Royal Avenue, Gays Mills, WI 54631 USA
Tel:[phone] • Fax[phone] • E-mail:[email protected] • Web:www.bapihvac.com
Specications subject to change without notice.
4 of 4
Installation & Operating Instructions
rev. 08/21/1728173_ins_CO2_Duct
CO2 Duct and Rough Service Sensor
Diagnostics
Possible Problems: Possible Solutions:
General troubleshooting Determine that the input is set up correctly in the controller's and building automation
software.
Check wiring at the sensor and controller for proper connections.
Check for corrosion at either the controller or the sensor. Clean off the corrosion,
re-strip the interconnecting wire and reapply the connection. In extreme cases,
replace the controller, interconnecting wire and/or sensor.
Check the wiring between the sensor and controller. Label the terminals at the
sensor end and the controller end. Disconnect the interconnecting wires from the
controller and the sensor. With the wires disconnected, measure the resistance from
wire-to-wire with a multimeter. The meter should read greater than 10 Meg-ohms,
open or OL depending on the meter. Short the interconnecting wires together at
one end. Go to the other end and measure the resistance from wire-to-wire with a
multimeter. The meter should read less than 10 ohms (22 gauge or larger, 250 feet
or less). If either test fails, replace the wire.
Check power supply/controller voltage supply
Disconnect sensor and check power wires for proper voltage (see specications on
page 4)
Incorrect CO2 Wait 15 minutes after a power interruption.
Check all BAS controller software parameters.
Determine if the sensor is exposed to an external environment different from the duct
area that is being measured.
If the sensor is reading consistently high, make sure that the power supply to the unit
can provide 240mA. A low power situation will cause high CO2 readings.
Note: If the CO2 sensor has consistently given high PPM readings for over 5 days, it
will take up to 14 days for the readings to return to normal.
For the sensor to work correctly, the wiring entrance must remain air tight. If
the CO2 transmitter is mounted to a hollow wall and wired through its back, or
wired with conduit, it is possible that a draft of clean air may ll the enclosure
through the wiring opening. This draft may prevent the unit from measuring
ambient CO2. BAPI recommends either a liquid-tight tting or plugging the
conduit at the enclosure.
• Liquid-Tight Fitting – BAPI’s Liquid-Tight Fitting (BA/LTF) allows wire
cables of 0.1 to 0.3 inch outside diameter to enter the box. Tightening the
collar onto the wire cable keeps the wiring entrance air tight.
• Conduit – Included with the CO2 transmitter is a foam plug to seal the ½
inch EMT. Place the wires into the plug as shown in Fig. 10 and then insert
the plug into the conduit sealing the conduit.
Fig. 10:
Wires Through Foam Plug
Keeping the Enclosure Air Tight After Termination