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VOC Sensor

VOC Sensor
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VOC Sensor p-type Metal Oxide This sensor is a broadband total VOC detector. When the cost of a PID is not justifiable, this sensor will detect VOCs with 10-50 ppb limit of detection, depending on the VOC. Unlike common n-type sensors, this metal oxide sensor has a large dynamic range, repeatable response, low humidity response and resistance increases in the presence of most VOCs. The change in resistance can be converted to an output voltage via a simple electrical circuit. Although the sensor can be used in constant temperature/ voltage mode, best response is achieved when the sensor is cycled between 400°C (sensing temperature) and 525°C (reset temperature). See our Application Note. PERFORMANCE Range ppm isobutylene limit of performance warranty 1 to 100 Sensor resistance (Ro) kQ (50% rh, 23 ± 20C) 220 ±45 Sensor resistance ratio (Rg/Ro x 100%) %; Isobutylene @ 10ppm in air 285 ±30 Gas response relationship (Rg/Ro - 1 = Xk x Concn) 0.5 +/- 10% (k for isobutylene) where ki = constant for gas i, n = 1 or 0.5 0.5 (n for isobutylene) Heater resistance (RH @ sensing temp.) Q (400 ±10oC) 22 ±3 Heater resistance (RH @ reset temp.) Q (525 ±10oC) 26 ±3 Heater power consumption (mW) typical for 5:1 VH = 2.7 ±0.2V (400oC) 340 ±30 Operating Temperature Range oC -20 to 120 SENSITIVITY TO OTHER GASES EtOH response % measured gas @ 10 ppm EtOH TBA Figure 1 Response from 0 to 20ppm Isobutylene Real time response at 20,1 0 and 5 ppm Isobutylene in 50% rh. Sensor operating in 2-temperature mode, pulsing between 400oC for 5 mins and 525oC for 1 min. Time (minutes) 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

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Real time response to 100, 50 and 25 ppm Ethanol in 50% rh. Sensor operating in 2-temperature mode, pulsing between 4000C for 5 mins and 5250C for 1 min. VOC Sensorp-type Metal Oxide Performance Data Real time response to 500, 250 and 100ppb Benzene in 50% rh. Sensor operating in 2-temperature mode, pulsing between 4000C for 5 mins and 5250C for 1 min. Response over a range of 10% - 90% rh air, operating in 2-temperature mode with a 5:1 cycle ratio of sensing (400oC) and resetting (525oC) For further information on the performance of this sensor, on other sensors in the range or any other...

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