Catalogs >
Alphasense >
COH-A2

COH-A2
4Pages

Catalog excerpts

COH-A2Carbon Monoxide Hydrogen Sulfide Introduction Personal gas safety monitors can be found in most industries, with the requirement for multiple gas detection becoming commonplace. Most of these gas detectors measure both Carbon Monoxide and Hydrogen Sulfide. Alphasense new 2sense H2S+CO gas sensor allows designers to reduce significantly their gas detector size and cost. The 2sense uses a patented approach to dual gas sensor design and utilises our also patented low Hydrogen sensitivity CO electrode A larger version of the D2 sensor, which has a proven track record in the field overmany years, the 2sense does not compromise performance or long term stability over the standard two-sensor solution when measuring both H2S and CO. PERFORMANCE Sensitivity nA/ppm in 400ppm CO 50 to 100 Response time t9o (s) from zero to 400ppm CO < 35 Zero current ppm equivalent in zero air -3 to +3.5 Resolution rms noise (ppm equivalent) < 0.5 Range ppm CO limit of performance warranty 1,000 Linearity ppm error at full scale, linear at zero and 400 ppm CO 10 to 40 Overgas limit maximum CO for stable response to gas pulse 5,000 LIFETIME Zero drift ppm equivalent change/year in lab air < 0.5 Sensitivity drift % change/year in lab air, monthly test < 4 Operating life months until 80% original signal (24 month warranted) 24 Zero @ -20oC ppm equivalent change from 20oC 0 to 5 Zero @ 50oC ppm equivalent change from 20oC 0 to -5 CROSS Filter Capacity ppm-hours of Hydrogen Sulfide 1200 SENSITIVITY H2S sensitivity % measured gas @ 20ppm H2S < 12 NO sensitivity % measured gas@ 50ppm NO < 100 SPECIFICATIONS Pressure range kPa 80 to 120 Humidity range %rh continuous (see note below) 15 to 90 Storage period months @ 3 to 20oC (stored in sealed pot) 6 Load resistor Q (recommended) 10 to 47 Note: Above 85% rh and 40OC a maximum continuous exposure period of 10 days is warranted. Where such exposure occurs the sensor will recover normal electrolyte volumes, when allowed to rest at lower %rh and temperature levels for several days. lXT At the end of the product’s life, do not dispose of any electronic sensor, component or instrument in the domestic waste, but contact the instrument manufacturer, Alphasense or its distributor for disposal instructions. NOTE: all sensors are tested at ambient environmental conditions, with 47 ohm load resistor, unless otherwise stated. As applications of use are outside our control, the information provided is given without legal responsibility. Customers should test under their own conditions, to ensure that the sensors are suitable for their own requirements. Alphasense Ltd, Sensor Technology House, 300 Avenue West, Skyline 120, Great Notley. CM77 7AA. UK Telephone: +44 (0) 1376 556 700 Fax: +44 (0) 1376 335 899 E-mail: sensors@alphasense.com Website: www.alphasense.com

Open the catalog to page 1

erformance Data Performance Data Carbon Monoxide Channel Figure 1 CO Channel Sensitivity Temperature Dependence Figure 1 shows the % variation in sensitivity caused by changes in temperature. The data is taken from a typical batch of sensors. Zero current, referenced to 20oC (equivalent ppm) Figure 2 CO Channel Zero Temperature Dependence 3 Figure 2 shows the variation in zero output caused by changes in temperature, expressed as ppm gas equivalent, referenced to the zero at 20oC. This data is taken from a typical batch of sensors. Figure 3 CO Channel Response to 800ppm CO 40000 Figure 3...

Open the catalog to page 2

COH-A2 Specification contdSpecification Hydrogen Sulfide Channel PERFORMANCE Sensitivity nA/ppm in 20ppm H2S 450 to 1000 Response time t90 (s) from zero to 20ppm H2S @ 20oC < 30 Zero current ppm equivalent in zero air ± 0.25 Resolution rms noise (ppm equivalent) < 0.1 Range ppm H2S limit of performance warranty 100 Linearity ppm error at full scale, linear at zero and 20ppm H2S <± 5 Overgas limit maximum ppm H2S for stable response to gas pulse 200 LIFETIME Zero drift ppm equivalent change/year in lab air < 0.1 Sensitivity drift %...

Open the catalog to page 3

erformance Data Performance Data Hydrogen Sulfide Channel Figure 5 H2S Channel Response to 25ppm H2S Figure 5 shows response to 25ppm H2S. Sensor shows a fast and stable response and recovery and repeatable sensitivity. Figure 6 H2S Channel Sensitivity Temperature Dependence 120 Figure 6 shows the % variation in sensitivity caused by changes in temperature. The data is taken from a typical batch of sensors. Figure 7 H2S Channel Zero Temperature Dependence Zero current, referenced to 20oC (equivalent ppm) Technical Specification Figure 7 shows the variation in zero output caused by changes...

Open the catalog to page 4