Catalytic Flammable Gas Sensors NP-17SH - NEMOTO - #1

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NEMOTOTECH S.r.l. – 20010 Cornaredo (MI) ITALY Via Legnano, 2 – Tel.+39.02.93544190 – Fax +39 .02. 93540347 C.F. e P. IVA (VAT) 03231490966 – CAPITAL . 36.000 EU – Website: www.nemototech.it – E-mail: info@nemototech.it TECHNICAL INFORMATION SHEET: NEMOTO NP-17SH Single Header Pellistor Gas Sensor General Description The Nemoto NP-17SH is a catalytic (pellistor) type flammable gas sensor supplied as a matched pair of pellistor elements mounted on a single header and protected by a metal mesh enclosure and can. The sensor detects and measures the presence of flammable gases and vapours in air, in the range 0- 60% of the Lower Explosive Limit (LEL) of the gas or vapour being measured. Designed as a lower cost alternative to the twin-header NP-17 device, yet an improvement from the NP-17S the NP-17SH may be used as the sensing platform in fixed flammable gas detection systems up to 150ºC. The NP-17SH exhibits excellent long term zero and sensitivity stability and a high level of resistance to catalytic poisons. The highly automated manufacturing procedure employed by Nemoto results in a repeatable reliable sensor which, unlike similar devices, requires no trimming resistor to enable the detector to be matched with a compensator. Nemoto has a policy of continuous development and improvement of its products. As such the specification for the device outlined in the data sheet may be changed without notice Specifications: Recommended Voltage: 2.0V +/- 0.1V Current Drawn: 170 +/- 20mA Zero Offset: 0mV +/- 30mV Sensitivity: 50-80mV/% CH4/Air Range: 0-60% LEL Accuracy: +/- 1%LEL(CH4) Maximum Long Term Drift: Span: < +/- 5% LEL/ 3 Months Zero: <+/- ½ mV/Month Response Time: T50: 3 sec T90: 8 sec Recommended Circuit: Note: The value R1 is arbitrary, since the function of R1 is to balance the bridge. 1K
is suggested. Temperature Range: -20°C to +150°C Temperature Drift: (-20°C to +70°C) Zero: < +/- 2%LEL Humidity: 0-100%RH, non-condensing Humidity Response: +/- 2%LEL Linearity: Effectively Linear to 60%LEL Test data on drift, poisoning, temperature performance, linearity will be available on the Characterisation Document np-17sh-CD. ds-np17SH, issue 1, May 2008