News — Sensor

Capnography is the measuring and monitoring of the carbon dioxide levels in exhaled breath. In healthy individuals, the difference between the CO2 exhaled and CO2 levels in arterial blood are proportional. Therefore, by monitoring the waveform of CO2 levels on a capnogram (an electronic capnography monitor) over time, medical personnel like anesthesiologists or paramedics can use the information to monitor a patient. Sudden changes in end-tidal CO2 (ETCO2, the level of carbon dioxide released at the end of expiration) may signify changes in a patient’s heart or lung functions. Non-dispersive infra-red (NDIR) CO2 sensors are at the heart of virtually...

This application note describes how to directly read and write data directly to the SenseAir K30 and K33 line of CO2 sensors. Please read the MODBUS specification document before reading this document to gain a background understanding on the sensor’s implementation of MODBUS and for checksum calculating algorithms. Using these commands opens up the entire EEPROM and RAM of the sensor for UART access. It will also allow us to access the sensor using the memory locations described in the I2C guide.

The Arduino makes an ideal platform for prototyping and data collection with the SenseAir K series of CO2 sensors. Arduino CO2 Sensor Application Note From Wikipedia: Arduino is a single-board micro controller to make using electronics in multidisciplinary projects more accessible. The hardware consists of an open-source hardware board designed around an 8-bit Atmel AVR microcontroller, or a 32-bit Atmel ARM. The software consists of a standard programming language compiler and a boot loader that executes on the micro controller. Arduino boards can be purchased pre-assembled or as do-it-yourself kits. Hardware design information is available for those who would like...