Product Specification
aSENSE VAV
CO2 / temperature sensor with built-in general
purpose controller
Article numbers: 040-8-0xxx
1.
General description of devices
The IAQ-sensor product aSENSE
VAV is used to measure indoor air carbon dioxide concentration and
temperature. It is a very flexible controller with programmable outputs for
both relay- and linear control of e.g. mixed air dampers, humidifier and fans.
The measured values are shown on the display
.
The linear output functions are pre-programmed for different ventilation
strategies for stand-alone control. The units can alternatively be connected to
common VAV (Variable Air Volume) controllers, or Direct Digital Control (DDC).
All functions can be modified from a PC with the RS232 communication cable.
|
Item |
aSENSE specification |
|
Measured gas |
Carbon
dioxide (CO2) |
|
Operating Principle |
Non-dispersive
infrared (NDIR) waveguide technology |
|
OUT1 MAX function
of CO2 and temperature |
0 - 10VDC, programmable output
pre-programmed as control signal of demand of coolness and air quality (with reduced flow by extreme cold) |
|
OUT2 CO2 |
0 - 10VDC, programmable output
pre-programmed 600-900 ppm CO2 |
|
OUT3 |
Relay pre-programmed ON/OFF 600/500 ppm CO2 |
|
OUT4 |
0 - 10VDC or open
collector, control signal of heat demand pre-programmed PWM, 18-20 °C, inverted input |
|
Accuracy CO2 |
± 1% of measurement range ± 5 % of measured value |
|
Response time (T1/e) CO2 |
< 3
min. diffusion time |
|
Pressure Dependence |
+1,6% reading per kPa deviation from normal
pressure, 100kPa |
|
Maintenance push
buttons |
Push button menus are available for configuration of
outputs e.g. set points |
|
Accuracy Temp |
±1°C |
|
Operation Temperature Range |
0-50 oC |
|
Operation Humidity Range |
0-85 %RH
(non-condensing) |
|
Operating environment |
Residential,
commercial1 |
|
Storage temperature |
-40 to
+70 °C (display models: -20 to +50 °C) 1 |
|
Dimensions wall mounted (mm) |
120 x 82 x 30 |
|
Dimensions duct mounted (mm) |
152 x 85 x 47 (Probe length: 245mm) |
|
Dimensions industrial housing (mm) |
152 x 85 x 47 |
|
Power supply |
24VDC or 24VAC (50 - 60Hz) ± 20%, half-wave
rectifier input |
|
Power consumption |
< 3 W
average |
|
Life expectancy |
>15
years 2, 5 |
|
Yearly drift |
<
+-150ppm @1000ppm 6 <
+-100ppm @0ppm 6 (can't
difine amount of drift during power-off)" |
|
Conformance with standards |
EMC
2004/108/EC directive EN
61000-6-1:2001 “Immunity for residential, commercial and light industrial
environments” EN
61000-6-3:2001 “Emissions standards for residential, commercial and light
industrial environments” RoHS
directive 2011/65/EU |
|
Serial communication |
UART (SenseAir
protocol standard) |
|
Maintenance |
No maintenance required as Auto Background
Calibration, ABC, is used. 2,4 |
Table 1: Key technical specification for the aSENSE VAV
Note 1: SO2
enriched environments are excluded.
Note 2: This device
generation of heat (self-heating due to power consumption) does not
influence/violate temperature accuracy
specification of this device, as long as CO2 measurement (lamp
blink) interval is ≥ 15s.
Note 3: Accuracy is specified over
operating temperature range. Specification is referenced to certified
calibration mixtures. Uncertainty of calibration gas mixtures (+-2% currently)
is to be added to the specified accuracy for absolute measurements.
Note 4: In normal IAQ
applications, accuracy is defined after minimum 3 weeks of continuous operation
with ABC.
Note 5: Repeatability is
included. Uncertainty of calibration gases (+-2% currently) is added to the
specified accuracy.
Note 6: Yearly drift
of unpowered sensor is not defined
Set point values of temperature (air cooling and
heating) and air quality (CO2) can be adjusted individually by the unit’s maintenance push buttons. When a set
point value is changed the control curves of that parameter are parallel
displaced! Out(1) controls both air quality and temperature but temperature
overrules so if the temperature sinks below the LIMIT value the air supply is
cut down. Two different gain alternatives can be used in the
temperature/cooling feed-back loop. In alternative 1 the P-band is 1
degree and in alternative 2 the P-band is 2 degrees (see figure 2).
Temperature compensation of the demand control is done for temperatures below
LIMIT value (see figure 4).
The standard configuration of aSENSE VAV, with its settings, is
typical in many Variable Air Volume (VAV) applications. Even other control
parameters can be programmed from the UIP software. There are a number of
different regulator blocks available:
6 programmable P-bands (linear functions) with associated set points, 2 additional
general purpose P-bands, plus 1 timer function regulator
controlled by the DI1-terminal are available. In addition, the different regulator
outputs may be mixed together using 3 multiplexer (4:1) blocks. To each of the
4 outputs 4 of the available functions can be addressed so that the sum, or the
largest value, is transformed to an output signal. The Out(1) and Out(2)
outputs can be limited within defined MIN and MAX values. These MIN and MAX
values can be set/updated from the push button menu under operation.
2.
Drawings
Figure 1 Housing of wall mounted sensors
Figure 2 Duct housing measured in mm and
(inches)
3.
Terminals and outputs description
The table below specifies cable
connections of the aSENSE VAV.
Figure 3 The aSENSE VAV PCB with jumpers and
terminal area enlarged at right
5.
Push Button
Operation for aSENSE VAV
This sensor has two push buttons, MENU and ESC, located
on the front panel behind the flip-down lid. The YELLOW LED will acknowledge a
successful push by a short flash. Wait until the LED is turned off before next
push. The push button MENU is available for
selection of display value or maintenance commands, whereas ESC is available to
escape back from a selected level.
Figure 4 The sensor with push
buttons Figure 5 The push button MENU is
pushed
Figure 6 The push button ESC Figure 7 The ENTER command is done
is pushed by pushing
buttons MENU and ESC
at the same time for about 14 seconds
Display
modes
In DISPLAY MODE the DEFAULT operation is that
the sensor alternates between temperature and carbon dioxide readings
presentation. The push button MENU(+) is used to select the indicated value on
the display to be the error code or
the set points of temperature and CO2. The display
will always return to the Default display mode after power up. If a permanent change of default values is
requested the PC software is to be used.
|
Function Line |
Display |
Time
limit |
Function
description |
|
0 |
Temperature / CO2 |
no |
DEFAULT -
Normal operation |
|
1 |
Exxx |
yes |
Error code.
If no error has been detected the code E0 is shown. The error code is reset
with Entr(+-). |
|
2 |
Present temperature and CO2. set points |
no |
Toggle
between display of temperature and CO2 set
point with MENU(+). |
Table
III. On the display without entering the maintenance menu
Maintenance
level
A number
of execution options are available from the MAINTENANCE MENU (see Table IV).
This level is accessed only from the display mode in the set points of temperature and CO2 selection. A two buttons push and an access code restrict access, intended for competent
trained service personnel only. The Entr(+-) command is done by PUSHING MENU
AND ESC AT THE SAME TIME (hold down for about 15 seconds). The access code has
eight binary digits; one press at MENU(+) equals 1 and one press at ESC(-)
equals 0. The code value can be changed for
your personal choice from the software UIP 4.3. The menu diagram in
detail is shown in the appendix.
Always
use the ESC button to return to the DEFAULT mode. Several pushes of the ESC
button may be needed to return to the DEFAULT mode. The Entr(+-)
push (MENU & ESC) eventually leads to execution of functions, which causes
temporary or permanently change of any parameter, that affects the system
outputs!
|
Function Line |
Display |
Time
limit |
Function
description |
|
3 |
ECxx |
yes |
Access code
to the service menu The default
value of the code is 255 (=11111111, that is eight presses on MENU(+)). Press
down MENU(+) and let it scroll until it stops. The last two digits of the
code are shown. Then ENTER to accept the selected code. |
|
4a |
SPt |
yes |
For
setting the temperature set point. |
|
4b |
The present temperature set point |
yes |
For increase / decrease of the temperature set
point. The set point is increased by
stepping with MENU(+) button. Decreasing is done by stepping with the ESC(-)
button. |
|
5a |
SPc |
yes |
For setting the set point of the CO2 concentration |
|
5b |
The present CO2 set point |
yes |
For increase / decrease of the CO2-concentration set point The set point is increased by
stepping with MENU(+) button. Decreasing is done by stepping with the ESC(-)
button. |
|
6a |
AOUt |
yes |
First step of adjusting
the analogue outputs MAX and MIN values |
|
6b |
An xx |
no |
Select
analogue output by stepping with MENU(+) button. |
|
6c1 |
SetL |
no |
Leads
to adjustment of the MIN value. |
|
6d1 |
The present MIN value in % of FS |
no |
Increase
the MIN value by stepping with the MENU(+) button. Decrease by stepping with
the ESC(-) button. The output is set to the MIN value and can be checked with
a multimeter. |
|
6e1 |
Sure |
no |
The
adjustment is saved by pressing Entr(+-). Press ESC to return without saving. |
|
6c2 |
SetH |
no |
Leads
to adjustment of the MAX value |
|
6d2 |
The present MAX value in % of FS |
no |
Increase
MAX value by stepping with the MENU(+) button. Decrease by stepping with the
ESC(-) button. The output is set to the MAX value and can be checked with a multimeter. |
|
6e2 |
Sure |
no |
The
adjustment is saved by pressing Entr(+-). Press ESC to return without saving. |
|
7 |
CALb |
yes |
Background calibration = CO2-sensor calibration with fresh air. An easy way to correct the zero
point error. The sensor needs fresh air (380-420
ppm CO2). The calibration must be confirmed
by pressing Entr(+-). |
|
7a |
Sure |
yes |
Confirm that a
background calibration shall be done. |
|
8 |
CAL |
yes |
Zero point calibration of the CO2 sensor. The sensor needs zero gas. See the
zero point calibration instruction. The calibration must be confirmed by
pressing Entr(+-). |
|
8a |
Sure |
yes |
Confirm that a
zero point calibration shall be done. |
Table IV. Maintenance functions available on aSENSE VAV to set output
limits. Time limit refers to an internal time-out that returns the LCD and
maintenance function back to normal. ENTER is a simultaneous pressing on MENU
and ESC.
PLEASE NOTE! If a power failure happens when the sensor has Out(1)...4
locked to min/max limits, then the sensor will have this output locked when the
power returns. It is necessary to enter this menu item and release the output
manually!
6.
Calibration
The aSENSE VAV are 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 7.5 days interval and slowly corrects for any long-term drift detected
as compared to the expected fresh air value of 400 ppm 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 30-50ppm/week.
A
Back-ground calibration is an easy way to correct a sensor’s zero point. The
sensor needs fresh air (380-420 ppm CO2).
A zero calibration can be performed by use of pure nitrogen or air that
has passed through a chemical absorber. When a zero calibration shall be
executed a plastic tube with 2.2 mm outer diameter and 0.8 mm inner diameter
shall be inserted in marked holes of the sensor. Plastic tubing is connected to
the tube. The gas flow should be between 0.3 and 1.0 l/min.
Figure 8 Part of the PCB with holes
for gas inlets marked
7.
Self-diagnostics
The system contains
complete self-diagnostic procedures. A full system test is executed
automatically every time the power is turned on. For aSENSE VAV the internal voltage
regulators and outputs are checked. In addition, constantly during operation,
the sensor probes are checked against failure by checking the valid dynamic
measurement ranges. All EEPROM updates, initiated by the sensor itself, as well
as by external connections, are checked by subsequent memory read back and data
comparisons. These different system
checks return error bytes to the system RAM. The error codes are available by
connecting a PC with a special RS232 cable connected to the UART port slide connector. The error codes are shown
in the software UIP (version 4.3 or later). Warm up and Out of Range
are the only bits that are reset automatically after return to normal state. All
other error bits have to be reset manually after return to normal state –
either by pushing MENU & ESC buttons simultaneously for =Entr(+-) or by power off and
restart.
By pushing the push button ”MENU” the error code number Exxx is shown on the LCD. Descriptions of the different codes
are listed below.
The
yellow LED flashes if an error has been detected. If a fatal error has been
detected the yellow LED is lit.
Error code and action plan
|
Bit # |
Error code |
Error description |
Suggested action |
|
0 |
N/A |
Fatal
Error
|
Try to
restart sensor by power OFF/ON. Contact local distributor |
|
1 |
2 |
Reserved
|
|
|
2 |
4 |
Algorithm
Error. Indicate
wrong EEPROM configuration. |
Try to
restart sensor by power OFF/ON. Check
detailed settings and configuration with UIP software version 4.3 and higher. Contact
local distributor. |
|
3 |
8 |
Output Error
Detected
errors during output signals calculation and generation. |
Check connections
and loads of outputs. Check
detailed status of outputs with UIP software version 4.3 and higher. |
|
4 |
16 |
Self-Diagnostic
Error. Algorithm
timeout |
Check
detailed self-diagnostic status with UIP software version 4.3 and higher. Contact
local distributor |
|
5 |
32 |
Out of Range Error
Accompanies
most of other errors. Resets
automatically after source of error disappearance. |
Try
sensor in fresh air. Check
connections of temperature and relative humidity probe. Check
detailed status of measurements with UIP software version 4.3 and higher. See
Note 1! |
|
6 |
64 |
Memory Error
Non-fatal
error during memory operations. |
Check
detailed settings and configuration with UIP software version 4.3 and higher. |
|
7 |
128 |
Warm Up state
Is
always set after power up or power failure. Resets after restart sequence. |
If it
doesn’t disappear in half a minute, check power stability. |
Table IV Error codes
Note 1. Any probe is out of range.
Occurs, for instance, during over exposure of CO2 sensor, in which case the error code will
automatically reset when the measurement values return to normal. Could also
indicate the need of zero point calibration. If the CO2 readings are normal, and still the error code
remains, the temperature sensor can be defect or the connections to it are
broken.
Remark: If several errors are detected at the same time
the different error code numbers will be added together into one single error
code!
PLEASE NOTE! The sensor accuracy is
defined at continuous operation (at
least 3 weeks after installation)
8.
Materials
|
Part |
Material |
Color |
Requirement |
Min. UL Rating |
|
Wall
mounted sensors |
Novodur P2H-AT |
White/Offwhite |
|
UL94-HB |
|
Duct
mounted sensor base |
Plastic PC/ABS Bayblend FR3000 |
Black |
|
Minimum UL94-5V |
|
Duct
mounted sensor tube |
Plastic PC/ABS Bayblend FR3000 |
Black |
|
Minimum UL94-5VB |
|
Cable
gland |
Plastic polyamide based |
Black |
|
UL94-V2 |
|
Duct
mounted sensor lid |
Plastic Polycarbonate Makrolon 6555 |
Transparent |
QMFZ2 |
UL94-V0 |
9.
User instructions
Please see
manuals.
10.
List of standards applied
Applicable standards:
EN 61326-1:2006 "Electrical
equipment for measurement, control and laboratory use"
Emission: EN 61326-1:2006 class B equipment
Immunity: EN 61326-1:2006. Tested for basic immunity
test requirements (table 1, part 6.2)
Compliant standards:
EN 61000-6-1:2001 " Immunity for residential, commercial and
light-industrial environments"
EN 61000-6-3:2001
"Emission standard for residential, commercial and light-industrial
environments"
Accordingly tests have been performed as
specified in the following standards:
|
Basic
standard |
Compliant |
Test
of |
|
CISPR
11:2007 |
Yes,
class B, group 1 |
Radiated
emission |
|
CISPR
11:2007 |
Yes,
class B, group 1 |
Conducted
emission |
|
IEC
61000-3-2:2005 |
Not
applicable. Note 1 |
Harmonics
at power terminals |
|
IEC
61000-3-3:2008 |
Not
applicable. Note 2 |
Flicker
at power terminals |
Note 1: Less than 75W.
Note 2: Unlikely to produce significant voltage fluctuations or flicker
|
Basic
standard |
Compliant |
Test
of immunity to |
|
IEC 61000-4-3:2006 |
Yes |
Radiated
Radio Frequency Fields |
|
IEC 61000-4-6:2008 |
Yes. |
Conducted
disturbances induced by radio frequency fields |
|
IEC 61000-4-4:2004 |
Yes.
|
Electrical
fast transients, Burst |
|
IEC 61000-4-5:2005 |
Yes.
|
Surge |
|
IEC 61000-4-2:1995 |
Yes.
|
ESD |
|
IEC 61000-4-11:2004 |
Yes.
|
Voltage
dips |
RoHS and SVHC: EN 50581. Technical
documentation for the assessment of electrical and electronic products with
respect to the restriction of hazardous substances.
The sensors
are marked with article number, connecting power, standard output
configurations, production date, the crossed-out wheeled bin of the WEEE
directive and the CE mark. The wall mounted sensors are marked with a label on
the inside of the lid. The terminal and jumpers are on a label in the top cover
of the sensor.
The PCB used in all these sensors has been tested for
EMC and passed the test. Test report for the PCB used in all these sensors is
Test report #10229P from Jan Linders Ingenjörsfirma. The test report is marked
K40 platform aSENSE™ /
Simple transmitter with and without display, aSENSE™-VAV / with and without display
aSENSE™-Duct/-Ind and aSENSE™-VAV-Duct/_ind.
All components on the PCB are RoHS compliant. Proof is
material declarations or declarations of conformity to RoHS from suppliers. All
housing parts are also RoHS compliant.
13. Internal production control
All PCBs are
individually calibrated and verified. After mounting in the housing all sensors
are finally tested.
SenseAir®
AB
|
SenseAir® North America |
SenseAir® Chengdu Gas Sensors
Ltd. |
Box 96
|
29030 SW Town
Center Loop East |
First floor
8th of Xingke Road |
|
Stationsgatan 12 |
Suite 202 - #169 |
Hi-Tech
Industry Park |
|
SE- 82060 Delsbo |
Wilsonville, OR 97070 |
Jinniu
district, Chengdu |
|
Sweden |
USA |
Sichuan
province |
|
|
|
China |
|
|
|
|
|
Phone: +46(0)653 – 71 77 70 |
Phone: +1 52.0.349.7686 |
Phone: +86-028 - 875 928 85 |
|
Fax: +46(0)653 – 71 77 89 |
|
Fax: +86-028 – 875 928 85 |
|
E-mail: info@senseair.com |
E-mail: infoamerica@senseair.com |
E-mail: info@senseair.asia |
|
Web page: www.senseair.com |
|
Web page: www.senseair.asia |
|
|
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Document |
Rev |
Page 3 (3) |