Questions tagged [gas-sensor]
The gas-sensor tag has no summary.
41 questions
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Air Quality Index from BME688 environmental sensor with new AVR 8-Bit MCU
The BME688 environmental sensor requires using the closed source library BSEC to get an Air Quality Index as it only provides the raw gas sensor resistance.
I'd like to use the sensor with for example ...
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MQ6 first time use with ESP32
I am using a MQ6 gas sensor and ESP32 dev board. The intent of this circuit is to have gas sensor sense the gas leakage and inform ESP32 to take further action.
Following is how, I am connecting the ...
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133
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Understanding Gas Sensor Output Voltage from Resistance Change
I'm working on an air quality monitoring system using MQ7, MQ131, and MQ135 gas sensors. I've explained the working principle to my professor, including how gas concentration changes the sensor's ...
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My MQ6 gas detector stops working properly after some time when using a battery
I've connected an MQ6 gas sensor to the output of a 78L05 5 V regulator, with its input connected to the + terminal of a Duracell 9 V battery. The DOUT pin of the MQ6 is connected to the - terminal of ...
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How to use SCD30 with ESP8266?
I'd like to use a SCD30 sensor connected to ESP8266. I know it's possible to use for example Adafruit library to connect SCD's to Arduino:
...
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What is the significance of this circuit?
It is a part of a sensor circuit on I2C lines. But why are MOSFETs being used to connect pull up resistors for I2C lines?
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Can a comparator be powered by 2 "positive" voltages in order to output a certain "low" voltage?
Can the "ground" pin of a comparator be connected not to the actual ground, but around 0.2 V above ground?
To provide a little context:
There is an oxygen sensor that is producing between 0-...
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How did my CO detector know it had reached EOL?
I was recently awakened by my CO alarm beeping. I take CO exposure very seriously and attended to the beeping immediately. It was not a CO concentration alarm, but rather an end of life alarm ...
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105
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Am I wiring this sensor / wheatstone bridge correctly?
I have a methane sensor (MP7227-DA) that gives the following schematic:
I've assumed R1 and R2 = (C) and (D) in the diagram, R3 and R4 are resistors which are equal and make up the other side of the ...
- 101
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Converting analog values to PPM: MQ135 and MQ131
I am making an air quality monitoring system that makes use of an ESP8266 and an analog extender ADS1115. The main problem is that I get analog values and don't know how to convert them to PPM without ...
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Does flowing or turbulent air affect gas sensors such as PM2.5 Laser dust sensors and NDIR sensors?
My project is to place a laser dust sensor to detect PM2.5 and an NDIR gas detector on a drone to measure air quality. My understanding is that these sensors work by shining a laser through a channel ...
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164
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How to get methane concentrations from MQ-4 sensor
I have an ESP8266 chip that is connected to an MQ-4 sensor. I need to get the concentration of methane in air, the problem is I can't find a way to convert the analog readings into ppm or any other ...
2
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1
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260
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I want to use a microcontroller with 3.3v outputs with a sensor that needs 3v. Do I need drive-voltage reduction resistors or will be ok?
I want to use a microcontroller with 3.3 V supply to interface with with an MP-7227-TC sensor that needs a 2.9 to 3.1 V supply voltage.
The sensor is driven by a single high/low conttol line from the ...
- 29
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193
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Spice code for a memristor-based gas sensor: node error
I have written Spice code for a memristor-based gas sensor but it is displaying a node error. The error and the code are attached as images:
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2
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Deriving TVOC value in ppb/ppm units
Our project requires a Total VOC value in ppb or ppm units. But the sensors on the market give relative resistance change. How can I derive the TVOC ppb/ppm value? Or I don't know if there is such a ...
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How does temperature compensation work for pellistors in Wheatstone bridge?
Pellistors are used to detect combustible gases. Basically, the gas is burned inside the pellistor and the heat released will change the resistance of the detection element. The concentration of the ...
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Measure capacitance of planar electrodes for sensing gas using Arduino/Nucleo board
I am looking to do post-grad research study next year in the sensory field for sensing gases like hydrogen, nitrogen or ammonia (not decided yet). So trying to understand what is out there and how ...
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231
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Seeking deeper understand of reading a schematic with an op-amp IC (AD-8574)
A couple days ago I was seeking some education on reading a schematic, I had great answers for replies and I feel like I am closer. What I am trying to get my head around is the use of a dual channel ...
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1
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132
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What are the components symbolized in these 4 highlighted areas of this schematic?
I am a beginner and I understand only the most basic portions of this schematic. Could someone smarter please help me understand the highlighted areas?
Source: Schematic was copied from page 4 of the ...
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3
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2k
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MH-Z19 calibration. What to do for a non-permanently powered device?
I have 2 MH-Z19 for measuring indoor CO2 calibration. One is running permanently on a Raspberry Pi, the other one on an Arduino Pro Micro on a handheld device that is turned on only when I want to ...
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128
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H2S Sensor with 1 PPB Lower Detection Limit
We're trying to create an IoT device that can detect/mesaure H2S in ambient air with a
lower detection limit of 1 ppb or 0.001 ppm
However, checking Digikey and other similar suppliers, I haven't ...
0
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2
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300
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VCC power fluctuation issue
I'm building a device that contains microcontroller (Arduino) and several other modules. What makes me worry is the fluctuation of voltage at the Vcc input of one of the modules. High level scheme of ...
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2
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Occupancy detector using the MQ-135 gas sensor
Is it doable to make an occupancy detector using the MQ-135 gas sensor (datasheet) for a small room by checking if the current CO2 value is (significantly) larger than the base value?
Apart from ...
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Driver circuit for Figaro FECS sensor - specifically FECS44-100
I need help designing a driver circuit for a Figaro ammonia sensor FECS44-100
I also have in my possession, the official evaluation module EM-FECS(A)
The schematic for this (on page 2 of the link) ...
- 59
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1
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336
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Measure benzene with an Arduino [closed]
So,
I need to measure the concentration of Benzene in air. I have an Arduino Zero to read analog or digital value.
I found out the sensor MQ-135. The problem is that, if I'm right, the sensor reacts ...
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2
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152
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Build electrical characteristic for gas measurament via IR sensor
I'm building a CO2 measurement unit via Arduino and I'm the phase of choosing the sensors.
I've found out this IR sensor that, thanks to an emitter with WL of 4.26um is able to output a voltage ...
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2
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60
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What technologies are used to fabricate gas sensors?
Different types of gas sensors exist.
Sensors that work with light or resistance sensors.
In general, what technologies are used to build sensors?
3
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3
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509
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Potentiostat Drift
I am trying to get this biased potentiostat to work. I have attached the circuit below. I am using the Alphasense Nitric Oxide NO-A4 sensor.
For the purposes of this example, you can ignore the Aux ...
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Gas sensor parameters
I've just found this sensor on Aliexpress, but the vendor says that he provides more information after the device is bought. There is no information on what sensors does this device feature. I can't ...
user188731
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Can MQ-135 Gas Sensor be used to make DIY CO2 level monitor?
So I am thinking of building an device to measure CO2 levels in the air DIY fashion as premade equipment costs upwards of 100$.
I have found some information on how to build such a device using ...
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1
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699
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Comprehending wiring data sheet for ME3 C2H4 gas sensor
I am humbly requesting an English translation of this image. The only thing I figured out is that the box on the top left is the ME3 sensor I am trying to connect to an Arduino. It has three pins, as ...
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What are my options to measure oxygen concentration in a high temperature wood burner flue gas?
I'd like to measure oxygen concentration in flue gas from my wood burner.
Lambda sensors are suitable but, even if relatively cheap, they need a control unit to keep working temperature and other ...
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Are there any reasons I shouldn’t use a nodemcu’s 3.3v pin with this component?
I have this Hydrogen Sulfide gas sensor and the datasheet says the supply voltage requires a regulated voltage with a min of 2.6v and max of 3.6v
I can’t find any datasheet for the nodemcu v3 (spent ...
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How can I measure a sensor's load resistance which is adjusted by a potentiometer?
I have this MQ136 sensor that comes with a shield. Like most of the MQ series of gas sensors, you can get them with or without a shield. Unfortunately, I've been unable to find a datasheet that ...
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0
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573
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Control variable external power supply with Arduino
I'm currently working on an air pollution controller project and I have a problem to control an external power supply to supply 5V, 1.5V or 0V to an MQ7 gas sensor.
Using the direct PWM output to ...
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101
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Is a buffer required for this gas flow sensor to ADC connection?
I'm designing part of an application that will consist of an Omron D6F-P0010A1 MEMS flow sensor. The analog output of the sensor will be connected to a TI ADS1114 ADC.
I'm trying to figure out from ...
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Can Mq4 sensor be used for smoke detection?
I wanted to ask if Mq4 can be used for fire smoke detection?
I read it have small sensitivity to smoke in the data sheet, but I wanted to know what is the least value in ppm for it to detect smoke ?
...
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201
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Mq4 sensor doesnt detect natural gas but detects cigarette lighter gas only! [closed]
I am working on a project for detecting natural gas of cooking stoves, I have tested several sensors but the mq4 sensor was the one that worked fine.
Now after about one month of using the sensor i ...
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3
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22k
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How to calculate Gas sensor PPM from analog readings?
I am new to Arduino and electronics in general.I am working on MQ 7 Gas sensor to test Carbon monoxide level. But the issue is i still can't grasp the concept of converting analog readings to PPM. I ...
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Simple circuit slowly powering down
I have a gas sensor module here, with a power led and a digital out led (which glows in case of successful gas detection) built in it....
A simple circuit here, just connected the vcc and ground of ...
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1
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660
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History and lineage of the MQ- series of MOS gas sensors? [closed]
MOS-type gas sensors (described below) have been around for almost a half-century. The original TGS-109 (Taguchi Gas Sensor 109) was introduced in about 1969!
From http://www.figaro.co.jp/en/company/...
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