G
AERASGARD
®
ACO
2
The maintenance-free microprocessor-controlled AERASGARD
®
ACO
2
is used to
detect the CO
2
content in air. This sensor is optionally available with or without
display. The measurement signals are converted into standard signals of 0 -10 V.
Optionally, this CO
2
measuring trans ducer can be supplied with switching output.
The CO
2
content of air is determined by a dual beam NDIR sensor (non-dispersive
infrared technology). The detection range of this CO
2
sensor is calibrated for
standard applications such as monitoring of residential rooms or conference
rooms. Room ventil ation on an as - needed basis, improvement of well-being and
customer benefit, increased comfort as well as a reduction of operating costs
by energy conservation are only some of the beneficial results of employing
AERASGARD
®
ACO
2
sensors.
A measuring system based on NDIR technology for CO
2
measurement consists
of a light source and a receptor. A certain range of wavelengths of light radiated
off by the source is damped respectively absorbed by CO
2
molecules in the
measured section. That damping is detected by the receptor.
TECHNICAL DATA:
Power supply: ........................ 24 V AC ⁄ DC
Average power consumption: ....... < 3 VA at 24 V DC
Sensor:................................. optical, dual beam sensor (NDIR),
with automatic self-calibration,
non-dispersive infrared technology,
dual beam measuring method,
including atmospheric pressure compensation
Measuring range: ....................
multi-range switching
(selectable via DIP switches)
0 … 2000 ppm; 0 … 5000 ppm; 0 … 10000 ppm
Output: ................................. 0 -10 V or
with potential-free changeover contact (24 V)
Measuring accuracy CO
2
: ......... ± 70 ppm plus 5 % of measured value
Pressure dependence: ............. < ± 0,5 % of measured value ⁄ kPa at
compensated versions (standard),
otherwise ± 1,6 % of measured value ⁄ kPa
(referred to standard pressure)
Temperature dependence:......... < 5 ppm ⁄ K (referred to 20 °C)
Long-term stability:................. ± 1 % of final value per year
Gas exchange: ........................ by diffusion
Warm-up time: ........................ ca. 1 hour
Ambient temperature: ............. 0 …+50 °C
Response time: ....................... ca. 1 minute
Electrical connection: .............. 0.14 - 1.5 mm
2
,
via screw terminals on circuit board
Enclosure: ............................. plastic, polyamide, 30 % glass-globe-reinforced,
with quick-locking screws,
colour pure white (similar RAL 9010)
Dimensions: ........................... 108 x 70 x 73.5 mm (Thor II)
Cable gland: ........................... M 16 x 1.5 ; including strain relief
Protective tube: ..................... metal, Ø 20 mm,
nominal length NL = 40 mm
Protection class: .................... III (according to EN 60 730)
Protection type: ..................... IP 65 (according to EN 60 529)
Standards: ............................ CE-conformity,
electromagnetic compatibility
according to EN 61 326 + A1 + A2,
EMC directive 2004 ⁄ 108 ⁄ EC
Optional: ............................... 8 - digit display, cutout 36 x14 mm (W x H),
for displaying actual CO
2
content
Connecting diagram
ACO
2
Connecting diagram
ACO
2
- W
Schematic diagram
ACO
2
ACO
2
- W
1
2
3
5
6
7
(ACO
2
-W)
min. max.
2000 5000 10000 aut
o
1 2 34
ON
ATM
Sensor plug
Set CO
2
Output CO
2
c
ont
ent
0-10V
UB+ 24V A
C/DC
UB- GND
Br
eak
er
Normall
y open
CO
2
range
Switching
threshold adjustment
Measuring range
selection CO
2
Button and LED
for manual CO
2
setting
Atmospheric
pressure sensor
1
2
3
5
6
7
UB- GND
UB+ supply voltage 24V AC/DC
Output 0-10V CO
2
-content in ppm
Breaker
Normally
open contact
changeover
(24 V)
1
2
3
UB- GND
UB+ supply voltage 24V AC/DC
Output 0-10V CO
2
-content in ppm
