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Low-cost catalytic pellistor gas sensor for residential / light commercial applications

NAP-56A explosive gas sensor


Detectable Gas:

Detection range:

Voltage supply:

Current drawn:

Signal Sensitivity:

Zero Offset (20oC):

Response time (90%):


Expected lifetime:

Long Term Span Drift:

Long Term Zero Drift:

All Flammable Gases

0 – 50% LEL

2.5V +/- 0.2V

170mA +/- 10 mA

15-23mV / 0.3% CH4

0mV +/-  35mV

< 10 seconds

+/- 1% LEL

> 3 years

<+/- 2% FSD/ month

<+/- 2mV / year

Operating Conditions

Operating temperature:

Humidity range:


Temperature Drift (zero):


-30 +70°C

0 – 95% RH

0.9 – 1.1 atm

<+/- 2% LEL

Effectively linear to 0-50% LEL

General Description:

The Nemoto NAP-56A is a new, improved low cost catalytic flammable gas sensor.

Closely related to the very popular NAP-55A sensor, the NAP-56A uses exactly the same sensing elements, but the enclosure in which they are mounted employs a nickel plated brass mounting cap and a phenolic resin header, instead of the Nylon 66 material used in the NAP-55A. As a result, the sensor exhibits an increased sensitivity output and an increase in useful temperature range, whilst being very slightly larger in dimensions, compared to the NAP-55A.

The widened temperature range of the NAP-56A makes it particularly suitable for applications such as recreational vehicles, caravans and marine applications where a wide temperature range is required. The mechanical construction and technical performance of this sensor makes it also suitable for a wide variety of Industrial and commercial gas detection applications.

  •        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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