Atest Gaz Sigma SmArt, User Manual

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3.2 Influence of temperature
Temperature changes have a very significant influence on the sensor characteristics – these changes can
lead to false alarms. Temperature impact models are very irregular, which makes good temperature
compensation very difficult.
3.3 Influence of pressure
Within the environmental parameters of the sensor, the influence of pressure on the measurement is
negligible.
3.4 Influence of moisture
Moisture changes clearly affect the sensor characteristics, while sudden changes can lead to false alarms.
Humidity impact models are very irregular, which makes good humidity compensation very difficult.
3.5 Influence of vibrations, impacts
Vibrations and impacts may cause damage of the sensor.
4 Factors shortening the lifetime of the sensor
Semiconductor sensors can operate from 5 to even 10 years. However, there are a number of factors that
can shorten their lifetime:
high concentrations of poisons, e. g. organometallic compounds, organophosphorus compounds,
sulphur compounds, halogen compounds, olefins,
silicone vapours absorb themselves on the surface of the sensor, gradually decreasing its
sensitivity. Avoid exposure of the sensor to silicone adhesives, silicone latexes, raising agents, oils,
greases,
high concentrations of corrosive gases (mainly NH
3
, H
2
S, SO
2
, HCl),
presence of concentrations well beyond the measuring range,
very dirty atmosphere or with constantly high humidity,
the strong non-linearity of the processing characteristics causes these sensors to work mainly as
leakage detectors:
Figure 2: Characteristic of semiconductor sensor
Atest-Gaz A. M. Pachole sp. j.
ul. Spokojna 3, 44-109 Gliwice, Poland
VAT No.: PL 9691433231
tel.: +48 32 238 87 94
fax: +48 32 234 92 71
e-mail: contact@atestgaz.pl
p. 4/4 Appendix: PU-Z-030-ENG R02
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