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Catalytic single-header pellistor flammable Gas Sensor for Industrial Environments

NCP-300S flammable gas sensor


Detectable Gas:

Detection range:

Voltage supply:

Current drawn:

Minimum Sensitivity:

Zero Offset (20°C):

Response time (90%):


Expected lifetime:

Long Term Span Drift:

Long Term Zero Drift:

All Flammable Gases

0 – 50% LEL

2.0V +/- 0.1V

300mA +/- 20 mA

40mV / % CH4

0mV +/-  30mV

< 8 seconds

+/- 1% LEL

> 3 years

<+/- 2% FSD/ month

<+/- 0.5mV / month

Operating Conditions

Operating temperature:

Humidity range:


Temperature Drift (zero):


-20 +60°C

0 – 95% RH

0.9 – 1.1 atm

<+/- 2% LEL

Effectively linear to 0-50% LEL

General Description:

The Nemoto NCP-300S is a catalytic (pellistor) type flammable gas sensor supplied as a matched pair of elements mounted on a single headers and protected by a metal mesh.  The sensor detects and measures the presence of flammable gases and vapours in air, in the range 0-50% of the Lower Explosive Limit (LEL) of the gas or vapour being measured.

Designed as a sensing platform for use in fixed flammable gas detection systems, the NCP-300S exhibits excellent long term zero and sensitivity stability and a high level of resistance to catalytic poisons. The device is intended as a lower cost alternative to the twin header NCP-300 and so is particularly suitable where where 2V, 300mA operation, with good performance at low cost, is essential.

The sensor also exhibits significantly higher signal output than its twin header cousin, giving higher accuracy at low gas levels, with good linearity to 60% LEL.

  •        Measures flammability directly

  •        Highly resistant to Catalyst poisons

  •        Resistant to shocks and vibration

  •        Effectively Linear output to 50%LEL

  •        Specific to flammable  gases

  •        Unaffected by Humidity

  •        Very Simple circuitry

  •        Very Low Long term drift

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