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│ 9 Appendix
COSH: carbon monoxide CO and hydrogen sulphide H
2
S
Type
electrochemical sensor (EC)
Use
PM 580/550/500
Measuring range
– CO:
0 – 300 ppm
– H
2
S:
0 – 100 ppm
Resolution
– CO:
1 ppm
– H
2
S: 0.5 ppm
Response times
– CO: t
50
< 12 s t
90
< 25 s
– H
2
S: t
50
< 11 s t
90
< 30 s
Warm-up time
< 120 s
Temperature range
-20 – 40 ºC
Measuring error
±3 % or ±3 ppm (±3 digits)
±5 ppm (long-term stability to EN 45544)
Drift
< 10% within 6 months
Interference
at 20 ºC
– 400 ppm H
2
:
< 55 ppm CO, < 1 ppm H
2
S
– 400 ppm CO: < 2 ppm H
2
S
– 20 ppm H
2
S:
< 8 ppm CO
– 100 ppm C
2
H
2
: < 200 ppm CO, < 2 ppm H
2
S
– 50 ppm NO:
< 50 ppm CO, < 10 ppm H
2
S
Humidity
5 – 95 % r.h., non-condensing
short term:
0 % r.h.
Lifetime
24 months (36 months expected)
Test gases
– zero point:
clean air
– Sensitivity:
40 ppm CO
40 ppm H
2
S
setting ranges:
– CO:
10 – 50 ppm
– H
2
S:
10.0 – 50.0 ppm
Humidity gas/test gas 5 – 95 % r.h., non-condensing
short-term:
0 % r.h.
error:
– 20 – 90 % r.h.: to /4/
Pressure
700 – 1200 hPa
error:
– 800 – 1200 hPa: to /4/
