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Special Low-range compact Hydrogen Sulphide (H2S) Sensor



Detectable Gas:

Detection range:

Maximum overload:

Output current:

Zero offset in air


Long Term Sensitivity drift:

Response time (90%):

Temp. depend. in air:

Expected lifetime:

Hydrogen Sulphide (H2S)

0 – 0.5 ppm

1 ppm

550 +/- 150 nA/ppm

+/- 0.1ppm  equivalent

+/- 1%

less than 2% /month

< 60 seconds

< 0.5 ppm (-20 to 50°C)

>2 years

Operating Conditions

Operating temperature:

Humidity range:


Recommended resistor:

Bias voltage:

-20 +50 degrees C

15 – 90% RH

0.9 – 1.1 atm

10 ohms

Not required

General Description:

The NAP-523 is an Electrochemical gas sensor with 3 electrodes for the detection of Hydrogen Sulphide (H2S).

The sensor has been specially designed to give a very high output signal, resulting a very low detection range of 0 to 0.5ppm, and a resolution (with high quality circuitry) of +/- 0.05ppm. The sensor is also insensitive to humidity changes and alcohol vapours, making it ideally suitable for measuring low levels of H2S on breath for health monitoring.

The Sensor can also be used in any application where very low Environmental levels of H2S need to be detected or monitored.

  •        3-Electrode design for greater stability

  •        Compact, leak proof enclosure

  •        Resistant to shocks and vibration

  •        Terminals may be soldered

  •        Linear output

  •        Highly specific to target gas

  •        Unaffected by alcohol vapours

  •        Low Power consumption

  •        Very Low Long term drift

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