S+S Regeltechnik AERASGARD KCO2 Operating Instructions, Mounting & Installation page 7

G
Mounting and Installation
ATTENTION!
The minimum CO concentration of outdoor air amounts to ca. 350 ppm
2
(output voltage = 1.75 V) in leafy, hardly industrialized areas. A sensor
self-test is initiated by above-atmospheric or below-atmospheric pres-
sure or by exposure of the sensor to more than 5000 ppm CO
output voltage (CO output) amounts to ca. 0.2 Volt during the self-test.
2
Gas inter-exchange in the sensor element happens by diffusion. Depend-
ing on changes in the CO concentration and flow velocity of the air sur-
2
rounding the sensor, the reaction of the device to changes in CO
centration may appear with a delay. It is absolutely necessary to choose
the device mounting position so that the air stream "presses" into the
duct tube. Otherwise, below-atmospheric pressure will develop in the
duct tube that may cause a substantial slow down of gas exchange or
even prevent it.
Automatic calibration of carbon dioxide measurement (default)
The device calibrates itself at an interval of 7 days. To ensure this
function, the device needs to be supplied with fresh air (CO
300 ... 400 ppm) at least for 10 minutes during each 7-day period. For
self-calibration, the devices memorises device-internally the CO
tent minimum value measured during a 7-day period. After 7 days, this
minimum value is standardised to 350 ppm CO
corrected accordingly. The maximum amount of correction is here limit-
ed to 40 ppm ⁄ interval.
Manual calibration of carbon dioxide measurement
Manual calibration can be started independently from the position of
the DIP 4 switch by pushing the button (probe 2). After connecting
the device, a period of at least 10 minutes of continuous operation of
the device at fresh air (CO content 300 ... 400 ppm) is to be ensured.
2
Manual calib ration of the output signal to 1.75 V (350 ppm = zero-point)
is started by pressing the button "Manual calibration CO
seconds). Preparing for calibration is indicated by a blinking LED. Setting
the output to 1.75 V at actual ambient conditions follows automatically
there after. During this phase, the LED is permanently activated. After
calibration is completed, the LED is deactivated.
Putting in operation
After switching on the device, a self-test and tempering period follows.
This procedure takes 3 to 5 minutes, depending on ambient conditions.
During this time, the output analog voltage differs from the actual meas-
ured value.
AERASGARD ® KCO – Duct CO
2
®
AERASGARD KTM - CO
Type ⁄ WG02 Measuring Range
CO
KCO - SD (invariably set)
2
K C O 2 - S D - U 0...2000 ppm
K T M - C O 2- S D - U 0...2000 ppm
K C O 2 - S D - I 0...2000 ppm
K T M - C O 2- S D -I 0...2000 ppm
KCO
(invariably set)
2
K C O 2 - U 0...2000 ⁄ 5000 ⁄ 10000 ppm
K T M - C O 2 - U 0...2000 ⁄ 5000 ⁄ 10000 ppm
K C O 2 - I 0...2000 ⁄ 5000 ⁄ 10000 ppm
K T M - C O 2 - I 0...2000 ⁄ 5000 ⁄ 10000 ppm
Note: This unit must not be used as safety-relevant device!
and the output signal is
2
2
sensors, Standard
2
– Duct CO measuring transducers, Standard
2 2
2
DIP switches
CO content (measuring range selectable) DIP 1
2
0...2000 ppm (default)
. The
2
0...5000 ppm
0...10000 ppm
CO calibration mode
2
con-
2
Automatic self-calibration
Manual calibration
content
2
con-
2
" (for ca. 5
Output
CO Temperature
2
0 - 10 V –
0 - 10 V 0 - 10 V
4...20 mA –
4...20 mA 4...20 mA
0 - 10 V –
0 - 10 V 0 - 10 V
4...20 mA –
4...20 mA 4...20 mA
DIP 2 DIP 3
O N OFF
O N
OFF
OFF OFF
DIP 4
Item No.
1501- 3140- 1000-400
1501- 3142- 1000-400
1501- 3140- 4000- 400
1501-3142- 4000- 400
1501- 3140- 1000-422
1501- 3142- 1000-422
1501- 3140- 4000- 422
1501- 3142-4000- 422
KCO
2
OFF
OFF
O N
O N
OFF