Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [gas]

28 questions
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1 answer

What (type of) sensor can detect odor of faeces?

"The Chemistry of the Smell of Toilets & Human Waste" has a really nice overview of the types of gases you want to detected if you're after building a toilet-clean-air detector. Hydrogen sulfide (H2S) sensors like MQ-136 are available for as little…
Marcel Stör
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4
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1 answer

determining sensitivity of carbon monoxide sensor

i'm working with a alphasense CO-AF sensor & i need to find out the CO quantity in ppm . i referred to the data sheet of the device and i dont know how to convert the given sensitivity specification to ppm.here is the link to the DATASHEET.can…
Rajat Asthana
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4
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1 answer

Why is it called a gas gauge?

Why are battery monitor ICs such as STC3115 (datasheet) called a gas gauge? This name seems pretty illogical and I was wondering the reasoning/story behind it.
EasyOhm
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Electrochemical Gas Sensor Potentiostat Circuit

I guess this is more of a review request than a specific question, but I was wondering if anyone has any experience with electrochemical sensors and the required circuits for gaining accurate measurements from them. Even if it's not specific to this…
RSA5000
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3 answers

MQ-135 Gas Sensor Interface

I want to interface MQ-135 air quality gas sensor. Sensor have 5V output interface. However my mcu work at 3.3V. I can basically put a voltage divider. But sensor itself is a voltage divider with a specific resistor range at output. So in this case…
cheour
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2 answers

Gas sensors for multiple gases

I have some questions about gas sensors: If I want to detect several gases at once, do I just need one sensor or will I need one sensor for each gas? How will I know which gas I am measuring? These questions are based from the datasheet of (for…
Laura Gonzalez
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1 answer

Spark gap breakdown voltage vs gap area

I've been trying to design a 1 MV hydrogen gas spark gap. I found the resistance of such to be in the range of 7 Ω/cm, not suitable for a target 40 kA current. Can I make the spark gap shorter without affecting the breakdown voltage? The electric…
Alessandro Mini
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How to calculate the pressure and velocity of an ionised gas that is being impelled with magnetic pressure

Calculating the velocity and pressure of an ionised gas based on magnetic pressure and magnetic force. Questions: Based on magnetic pressure expressed on an ionised gas, how do I calculate the current flow in amperes? The magnetic field is…
Milton L. Rowlands
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1 answer

MQ Gas sensors - can heater coil be run 24/7?

I am building a Hydrogen Sulphide gas detector for battery charging rooms using a MQ-136 sensor. I have searched everywhere for the answer to this question:- Can the sensor be powered continuously? I saw a forum comment (in french) on stack exchange…
Adrian Smith
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Power plant cost accounting

For a 300 MW power plant, 14.5 MJ / kWh of heating capacity must be provided. For this you can use coal with a heating value (hW) of 29 MJ / kg and a price (P) of 35 € / t or gas with a calorific value of 36 MJ / m3 and one Price of 90 € / 1,000 m3.…
otto
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My gas sensor is stuck physically, how can I fix it?

I'm not sure if this is the right area, but it's a problem with one of my components physically. When I press on both sides, it doesn't come up. Is there any way that I can get this 'up' cosmetically without taking it apart? Thanks!
Blake
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Are gas bubbles ok in Flooded lead acid battery charging?

I Have HBL power system's 2cell 4.2v lead acid battery which has capacity of 12Ah for C/ 100 and 9Ah for C/10. I found it in the rubbish and thought it may useful and in working condition.I refilled it with dilute sulphuric acid. I charged…
Ridham
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Problem with biased circuit for oxygen sensor (SGX EC410)

I have designed a circuit for an SGX EC410 oxygen sensor by using these application note -PAGE 4, FIGURE 4 - (http://www.sgxsensortech.com/content/uploads/2014/08/A1A-EC_SENSORS_AN2-Design-of-Electronics-for-EC-Sensors-V3.pdf). When I try to measure…
Viktor Scherf
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How can I read a thermocouple situation with an ESP32

The thermocouple has two pins (a ground, a 0 to -0.0004 when activate the bobbin to run the gas.) I want know how can I detect whether the gas is open or not without adding a sensor to the system. Can I do it by amplifying the voltage or something…
ahmad reza safari
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Reactive power fluctuation

We have 6 Caterpillar gas generators 3520c. One of them when synches with the grid. Its kVAR fluctuates over wide range and the aux voltage too and the excitation volt and current. We checked AVR and easy gen (it's for control). What we can check…
ahmed mady
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