West Systems Portable diffuse flux meter, Руководство пользователя

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10 WS-TOX-H2S Hydrogen sulfide detector
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WS-TOX-H2S Hydrogen sulfide detector
Pin Signal
1 Gnd
Legend
2 +VDC
Gnd: Ground reference for power supply and RS485
3 Gnd
+VDC: 10-28 Volts Power supply input
4 RS485-B
RS485-A: Digital signal output A
5 RS485-A
RS485-B: Digital signal output B
6 Gnd
7 +12V
8 Gnd
9 RS485-B
Sensor specifications
Ambient conditions:
Air temperature -30°C to 50 °C
Air pressure 800 hPa to 1200 hPa
Air RH 15% ... 90% non condensing
Expected sensor life > 24 months
Chemical cell order code: WEST H2S-BH
Detector order code: WEST TOX-05-H2S-BH
Factory calibration : 25 ppm
RMS Noise < 0.02 ppm
Zero Offset < ±0.05 ppm
Max Overrange 200 ppm
The chemical cell reaction is:
The gas sample specific consumption is very low:
2.5 x 10
-10
moles/sec per ppm
Due to this consuption the H
2
S flux is methodically understimated by a -10%
with the accumulation chamber A and by a -5% when using the accumulation
chamber B. For this reason we recommend using the accumulation chamber B
except when the flux is very low.