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ATEX & IEC Certified Explosion Proof Flammable Gas Detection Head

General Description:

The Nemoto NCH-180 is a new low cost catalytic flammable gas sensor fitted within a certified Flameproof enclosure.

Using the popular NAP-56A sensor, the NCH-180 offers the excellent detection performance, stability and long life you may expect from a Nemoto Pellistor Gas Sensor, but may also be used in hazardous locations when coupled with a suitable certified Flameproof Junction Box.

The NCH-180 is remarkably compact compared with other similar Ex certified devices, with the sensor contained within the same barrel as the mounting thread, resulting in a very ergonomically elegant design, mounting flush to the junction box wall.

NCH-180 gas detection head


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 – 100% LEL

2.5V +/- 0.1V

180mA +/- 20 mA

20mV / % CH4

0mV +/-  30mV

< 30 seconds

+/- 1% LEL

> 5 years

<+/- 8% FSD/ year

<+/- 2mV / year

Operating Conditions

Operating temperature:

Humidity range:


Mounting Thread


-20 +70°C

0 – 95% RH

0.9 – 1.1 atm

M20 -1.5mm pitch

Effectively linear to 0-100% LEL

  •        Certified Explosion proof (ATEX + IEC)

  •        Measures Flammability directly

  •        Highly resistant to catalyst poisons

  •        Resistant to shocks and vibration

  •        Specific to flammable gases

  •        Unaffected by Humidity

  •        Very simple circuitry

  •        Very low long term drift

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