Dräger Polytron 7000 User Manual

121
Metrological certificate of approval
Information on DrägerSensor O
2
-LS (6809630)
Cross sensitivities
The table shows the reactions of the sensor to other gases than the measured gas (cross sensitivities). The listed val-
ues are typical and are valid for new sensors. The table does not lay a claim on completeness. Gas mixtures can be
displayed as the sum of all components. Gases with negative sensitivity can cancel out a positive sensor display. The
influence of the O
2
displacement is in not taken into account in the table.
Example:
With 2 Vol.-% ethylene in the air – measurement value deviation due to cross sensitivities (table value) = –1 Vol.-% O
2
O
2
displacement caused by 2 Vol.-% ethylene (2% of 20 Vol.-% O
2
) = –0.4 Vol.-% O
2
Polytron transmitter display (20.9 – 1 – 0.4) = 19.5 Vol.-% O
2
.
Principle of measurement: The DrägerSensor O
2
-LS (6809630) is an electrochemical three-electrode-sensor for measurement of
oxygen (O
2
) in air. The sensor can only be operated in connection with a suitable Dräger transmitter.
The sensor cannot be used for oxygen measurements in the presence of helium!
Reaction at the measuring electrode: O
2
+ 4 H
+
+ 4 e
–
=> 2 H
2
O
Reaction at the counter-electrode: 2 H
2
O => O
2
+ 4 H
+
+ 4 e
–
Ambient conditions:
Operational Characteristics -40
o
C to 60
o
C, short-term up to 65
o
C
700 hPa to 1300 hPa
5 to 95 % relative humidity, non condensing
storage (in original packaging) 0
o
C to 40
o
C
Measured value time setting:
t
0...20
: <12 seconds
t
0...90
<30 seconds
Calibration:
Flow rate: 0.5 L/min
Zero gas Nitrogen (99.9 Vol.-% N
2
)
Calibration gas Oxygen / nitrogen - mixed gas
Warming-up time:
Sensor is ready to operate after ≤90 minutes
Sensor is ready to calibrate after ≤6 hours
Gas / vapour Chemical symbol Gas concentration Measurement value devia-
tion in Vol.-%
with dust filter
acetaldehyde CH
3
CHO 50 ppm no influence
acrylonitrile H
2
C=CH–CN 80 ppm no influence
ammonia NH
3
50 ppm no influence
arseniuretted hydrogen AsH
3
3 ppm no influence
butadiene CH
2
CHCHCH
2
50 ppm no influence
tert-butylmercaptane (CH
3
)
3
CSH 4 ppm no influence
chlorine Cl
2
8 ppm no influence
hydrogen chloride HCl 20 ppm no influence
hydrocyanic acid HCN 20 ppm no influence
boroethane B
2
H
6
5 ppm no influence
1.1-dichloroethane C
2
H
4
Cl
2
50 ppm no influence
diethylamine (C
2
H
5
)
2
NH 100 ppm no influence
diethyl ether (C
2
H
5
)
2
O 400 ppm ≤ 0.1 (–) *
epichlorhydrine C
2
H
3
OCH
2
Cl 35 ppm no influence
ethanol C
2
H
5
OH 250 ppm no influence

Dräger Polytron 7000 Specifications

General

Brand	Dräger
Model	Polytron 7000
Category	Adapter
Language	English