27904 Parallax Inc, 27904 Datasheet
27904
Specifications of 27904
Related parts for 27904
27904 Summary of contents
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... Methane (CH4), 27931 detects Carbon Monoxide (CO), 27932 detects Propane (LPG) and 27904 detects Alcohol (C2H5OH). Interfacing with these sensors is done through a 4-pin SIP header and requires two I/O pins from the host microcontroller. The sensor modules are intended to provide a means of comparing gas sources and being able to set an alarm limit when the source becomes excessive ...
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... Switching circuit for the Propeller chip. Note: HIGH signal is required to turn on heater due to inversion of signal by the transistor. Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page chip, a 3.9 kΩ (10 kΩ could be used) resistor would be TM ...
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... The section below describes how to configure these gas sensor modules to detect gas with minimal calibration. Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page Function Alarm output to host microcontroller Heat switch input from microcontroller, active low ...
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... Note: Temperature and humidity are factors that could affect the sensor, making calibration difficult. If this should happen try adjusting the voltages used in the calibration up or down as necessary to find a more stable range. Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page Please note that turning the ...
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... Go to http://www.parallax.com, type the specific product number into our search box and click “GO.” For gas calibration information you can also visit the following PDF on this website: http://www.gotgas.com/pdf/GasSnsrCalibratn.pdf Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page ...
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... DEBUG " ENDIF LOOP UNTIL index = 0 LOOP Copyright © Parallax Inc. Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page The sensor should run for at The DEBUG screen will count down the 60 seconds ' Heater Switch Control ' Alarm Input Sense ' Counter Variable ...