
CO2 transmitter for air ducts, 80 mm probe, incl. cable gland AMC-1
CO2 transmitter for air ducts, 160 mm probe, incl. cable gland AMC-1
CO2 transmitter for air ducts, 160 mm probe, incl. display
Conduit connector: NPT thread
SDC-C1 Duct CO2 Transmitter
Features
CO2 measurement for air ducts
Minimum and maximum value memory
0…10V, 0…20mA or 2…10V, 4…20mA measuring signals
selectable with jumpers
Optional alternative signal ranges programmable
May be used as simple P-controller
Selectable averaging signal
Optional internal or external display (-OP or OPU-S)
Status LED
Applications
Demand based ventilation for homes and offices based on
measurement of the CO2 concentration.
Preset standard measuring range 0...2000 ppm, max.
possible range 0...5000 ppm.
Recording of minimum and maximum limits for critical environments
Direct control of extraction fan.
CO2 transmitter
The CO2 concentration is measured through non-dispersive infrared (NDIR) waveguide technology with ABC automatic
background calibration algorithm. The applied measuring technology guarantees excellent reliability and long term stability.
The microprocessor samples the CO2 once per second. It calculates an averaging signal over a preset number of seconds and
generates the output signal.
The output signal range and type may be customized by jumpers and if required by a programming tool. Standard signal
ranges are 0…10 VDC, 2…10 VDC, 4…20 mA and 0…20 mA. These ranges can be set by jumpers. Other ranges can be set by
using the internal or external display and programming module. (-OP or OPU-S)
Automatic baseline calibration ABC
The ABC background calibration constantly supervises the measured CO2 concentrations. The calibration function expects the
CO2 values sink to 400 ppm when the room is not occupied. Over a period of several days the controller tries to reach this
value step by step through recalibration of 30ppm per day max. In order to reach the given accuracy, it is required that the
Sensor is for at least 3 weeks in operation.
Note: The ABC calibration works only in those applications where the CO2 concentration sinks regularly to fresh air levels of
400 ppm. For special applications such as green houses, animal farms, etc. the ABC calibration should be de-activated and
the sensor should be manually calibrated. The automatic calibration can be deactivated through the external operation
terminal. The Sensor can be calibrated by the client and does not need to be sent in for calibration. See last page for details.
Minimum and maximum values
Using a display and programming accessory, the user has the option to read out and reset minimum and maximum values.
The minimum and maximum values may as well be used as output signals. The minimum and maximum values are saved into
the EEPROM and are available after a power interruption.
Ordering
Accessories
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24 VAC 50/60 Hz ± 10%, 24 VDC ± 10%
SELV to HD 384, Class II transformer, 48 VA max
For wire 0.34…2.5 mm2 (AWG 22…13)
Non-dispersive infrared (NDIR) waveguide technology
with ABC automaticbackground calibration algorithm
± 20 ppm ± 1 % of measured value
± 30 ppm ± 3 % of measured value
+ 1.6% reading per kPa deviation from normal
pressure, 100 kPa
Analog outputs
Output signal
Resolution
Maximum load
DC 0…10 V or 0…20 mA
10 Bit, 9.7 mV, 0.019.5 mA
Voltage: ≥1kΩ, Current: ≤250Ω
Operation
Climatic conditions
Temperature
Humidity
To IEC 721-3-3
class 3K5
0…50 °C (32…122 °F)
<95% RH non-condensing
Transport and storage
Climatic conditions
Temperature
Humidity
Mechanical conditions
To IEC 721-3-2 and IEC 721-3-1
class 3K3 and class 1K3
-30…70 °C (-22…158 °F)
<95% RH non-condensing
class 2M2
conformity
EMC Directive
2004/108/EC
EN 61 000-6-1/ EN 61 000-6-3
Degree of protection
Dimensions (H x W x D): Transmitter:
Probe:
68 x 91 x 47 mm (2.7” x 3.7” x 1.9”)
14 x 157 mm ( 0.55 x 6.2”)
Technical Specification
Safety advice. This device may only be installed and configured by a skilled electrician. Where a device failure endangers
human life and/or property, it is the responsibility of the client, installer and designer to add additional safety devices to
prevent or detect a system failure caused by such a device failure.
Dimensions mm (inch)
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Calibration end: Constant light for 10s. Success is
Red blinking: failed. Device enters error mode.
Installation
See installation sheet no. 70-000573 (www.vectorcontrols.com).
Configuration
Output signal configuration
The analog output signal type may be configured with a jumper for 0…10 VDC or
0…20 mA control signals. The jumpers are located next to the terminal connector
of each analog output. See table below for jumper placement. The factory setting
is to 0…10 VDC.
The signal range may be set with JP4 for both analog outputs. JP4 will only operate
if the output range specified with OP01 and OP02 is left at the default position of
0…100%. With any other setting the position of JP4 has no influence and the range
defined with the output parameters applies.
Jumper settings
0…10V, 2…10V
I1
U1: 2…10V
No light: no power or unit damaged
5 sec blinking: Normal
Constant light: Error mode
Alternate in 2 sec interval with air quality LED:
Calibration is active.
shown on air quality led: Green blinking: OK,
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Enable display of air quality LED on front
Samples taken for averaging control signal
Minimum CO2 range ppm
(concentration when output is at its minimum
Maximum CO2 range ppm
concentration when output is at maximum)
Level for medium CO2 concentration (orange light)
Level for high CO2 concentration (red light)
Enable ABC automatic background calibration
Calibrate CO2 sensor. Note: For normal operation, calibration is not
required. Only experts should calibrate the sensor.
0 = No calibration (default)
1 = Calibrate to gas (0 ppm)
2 = Calibrate to fresh air (400 ppm)
AO1: CO2: Configuration of output signal:
0 = Feedback CO2 input
1 = Feedback CO2 minimum value
2 = Feedback CO2 maximum value
AO1: CO2: Minimum limitation of output signal
AO1: CO2: Maximum limitation of output signal
Parameter configuration
The transmitter can be adapted to fit perfectly into any application by adjusting the software parameters. The parameters are
set with the operation terminals OPC-S or OPU-S. The OPU-S may also be used as remote indicator.
For correct display version 1.4 is required.
Input configuration
Output configuration
Use as P-controller
The CO2-transmitter may be converted into a proportional fresh air controller through a simple change of two parameter
settings:
Set a minimum concentration when the fresh air fan should start to run at its minimum speed; for example 500 ppm. Set this
as the minimum value in IP03 parameter. Then define the value when the fan should run at full speed, for example 1000 ppm
and set this value in IP04. Your transmitter has now been converted into an air quality P-controller!
The fan will start to run if the CO2 concentration is higher than 500 ppm. It increases to its maximum when CO2
concentration reaches 1000 ppm.
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Calibration
The default sensor OEM unit is maintenance free in normal environments thanks to the built-in self-correcting ABC algorithm
(Automatic Baseline Correction). This algorithm constantly keeps track of the sensor’s lowest reading over a 7 days interval
and slowly corrects for any long-term drift detected as compared to the expected fresh air value of
400ppm CO2.
Rough handling and transportation might, however, result in a reduction of sensor reading accuracy. With time, the ABC
function will tune the readings back to the correct numbers. The default “tuning speed” is however limited to about 30
ppm/week. For post calibration convenience, in the event that one cannot wait for the ABC algorithm to cure any calibration
offset, jumper 3 is provided for the operator to choose calibration options. There are two calibration possibilities: 0 ppm and
400 ppm. Only one calibration needs to be performed.
Advice: If you decided that a calibration is required and the duct sensor is placed in the fresh air stream, observe that the
Sensor housing is closed and that the openings on the sensor face the air stream. The sensor is located inside the cover. Only
placing the probe in the air stream with the cover open, will not provide fresh air on the sensor.
Calibration to 0 ppm with CO2 free gas
1. Connect the sensor on top with a tube (soft tubing 2x4 mm) and a nipple (nylon
tubing 30x0.8x2.2 mm), see picture on the right side. There are 2 alternative
positions for nipple attachment.
2. Let a gas mixture which is free from CO2 (i.e. Nitrogen or Soda Lime CO2
scrubbed air) flow into the sensor through the applied tube. The flow shall be in
the range of 0…1.0 liter/minute during 3 minutes. Keep the gas mixtures
flowing during the whole procedure.
3. Connect OPU-S, Login and set IP08 = 1 and exit configuration mode. The air
quality LED will blink in red color alternating with the status led in 2 second
intervals.
4. The sensor will now wait for a stable concentration. Once the calibration has
been executed, the status LED will show constant RED and the green air quality
led will blink for 10s if successful. If calibration is not successful (no stability of
concentration for 5 min, no communication with sensor) the red air quality led
will blink instead and the sensor enters error mode. Recalibrate or restart
device to stop error mode.
5. Verify the zero calibration using the OPU-S or the analog outputs. They should show 0 ppm CO2.
6. If zero calibration is not executed (sensor detected unstable gas concentration) wait 10 seconds and repeat steps 3
and 4 again. Do not breathe on the sensor!
Calibration to 400 ppm (fresh air)
1. Expose the active sensor for at least 5 minutes to fresh outside air.
2. Connect OPU-S, Login and set IP08 = 2 and exit configuration mode. The air quality led will blink in green color
alternating with the status led in 2 second intervals.
3. The sensor will now wait for a stable concentration. Once the calibration has been executed, the status LED will show
constant RED and the green air quality led will blink for 10s if successful. If calibration is not successful (no stability
of concentration for 5 min, no communication with sensor) the red air quality led will blink instead and the sensor
enters error mode. Recalibrate or restart device to stop error mode.
4. Verify the calibration using the OPU-S or the analog outputs. They should show 400 ppm CO2.
5. If unsuccessful, wait at least 1 minute before repeating the procedure again. Make sure that the sensor environment
is steady and calm!
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