How do carbon monoxide detectors work?

kyorge6293

I am trying to create a detector to see how much carbon monoxide is in a room. I am looking to find an specific average throughout a day, not just if the carbon monoxide level is too high.
By the way, I am doing a project on Indoor Air Pollution.
Thanks in Advance.

Answer
Most Carbon Monoxide detectors determine the amount of CO present in the air by using an electrolytic sensor. If the value is high, the alarm sounds.

There are digital CO detectors available which will read you the level on an LED number display. You can write down the numbers on the display at predetermined intervals and average them after 24 hours has passed. Most houses should read 0 all of the time. I've only seen mine say something other than 0 when I was working on the car in the garage and had it running for a couple minutes (with the garage door open although still allowed enough into the house to cause it to display, but not alarm). Take a look just past halfway down this page and you will see a couple models with a digital readout on them:

http://www.firstalert.com/CarbonMonoxideAlarmsCatalog.aspx

Oxygen and Carbon Monoxide instruments?

Q. I need to read levels of gas. What am I looking for?

Answer
Industrial Scientific sell T80 and T82 carbon monoxide monitors. They are a little bigger than a packet of cigarettes and can be worn by the user. The T82 has a data logging function as well as the usual Peak, STEL, TWA values.

The unit (I think) can do oxygen with a change of sensor.

It is also possible to get multiple detectors in a single unit. Combined CO, O2, H2S and LEL measuring units are common.

Search on the web for "T82 carbon monoxide monitor" to get a local safety supplier.

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How do sensors work? I need slightly technical information?

carbon monoxide detector values image

nandiana20

I'm doing this paper on wireless monitoring and I really need to know how sensors basically work and more specifically how temperature ,pressure ,light,radiation, force and toxic gas sensors work. I'm not an electronics student. So an extremely simple explanation would be helpful.

Answer
It is a HUGE field, so you will have to do some web searching. Manufacturers pages are usually good places to find explanatory info.

Temperature:
Thermocouple - makes use of the fact that a junction of 2 different metals produces a voltage difference which varies with temperature.
Thermistor - a resistor whose value changes with temperature. There are 2 types, PTC and NTC, positive / negative temperature coefficient.

Pressure:
Typically you have a silicon membrane with a force sensor (strain gauge) on it. Pressure on one side of the membrane causes it to distort, which causes a change in resistance in the sensor.

Light:
Photodiode - a diode that leaks current according to how much light falls on it.
Light-dependant resistor (LDR) - does what it says!

Radiation:
Ionisation type detectors - basically a gas-filled tube. When a radiation particle strikes a gas atom it creates an ion, or charged atom. An electric field attracts the ion to a plate, where it is detected as a pulse of current.
Scintillation detector - use a crystal that produces a flash of light when struck by a particle. The flas is detected by a light sensor.

Force:
Strain gauge - a thin film of resistive material. Resistance changes when it is flexed.
Force sensing resistor (FSR) - resistance changes when squeezed
Piezoelectric bimorph - produces a voltage when flexed

Toxic gas:
Carbon monoxide detectors...
http://en.wikipedia.org/wiki/Carbon_monoxide_detector

What would be a good intruder alarm system (sans video) VALUE FOR MONEY wise?

i know there are motion detectors, glass break sensors, door/window sensors and video. i know too that there are auto dial systems. heat and carbon monoxide sensors.

but i just want the simple door/window sensors & motion detectors with dial feature thank you!

Answer
the simplest one is the G.E. Simon XT. It is a wireless, self-contained, user-friendly alarm system that dials out and is, in my opinion, the easiest one for a regular person with no alarm technician experience, to program.

Powered by Yahoo! Answers

How do sensors work? I need slightly technical information?

carbon monoxide detector values image

nandiana20

I'm doing this paper on wireless monitoring and I really need to know how sensors basically work and more specifically how temperature ,pressure ,light,radiation, force and toxic gas sensors work. I'm not an electronics student. So an extremely simple explanation would be helpful.

Answer
It is a HUGE field, so you will have to do some web searching. Manufacturers pages are usually good places to find explanatory info.

Temperature:
Thermocouple - makes use of the fact that a junction of 2 different metals produces a voltage difference which varies with temperature.
Thermistor - a resistor whose value changes with temperature. There are 2 types, PTC and NTC, positive / negative temperature coefficient.

Pressure:
Typically you have a silicon membrane with a force sensor (strain gauge) on it. Pressure on one side of the membrane causes it to distort, which causes a change in resistance in the sensor.

Light:
Photodiode - a diode that leaks current according to how much light falls on it.
Light-dependant resistor (LDR) - does what it says!

Radiation:
Ionisation type detectors - basically a gas-filled tube. When a radiation particle strikes a gas atom it creates an ion, or charged atom. An electric field attracts the ion to a plate, where it is detected as a pulse of current.
Scintillation detector - use a crystal that produces a flash of light when struck by a particle. The flas is detected by a light sensor.

Force:
Strain gauge - a thin film of resistive material. Resistance changes when it is flexed.
Force sensing resistor (FSR) - resistance changes when squeezed
Piezoelectric bimorph - produces a voltage when flexed

Toxic gas:
Carbon monoxide detectors...
http://en.wikipedia.org/wiki/Carbon_monoxide_detector

What would be a good intruder alarm system (sans video) VALUE FOR MONEY wise?

i know there are motion detectors, glass break sensors, door/window sensors and video. i know too that there are auto dial systems. heat and carbon monoxide sensors.

but i just want the simple door/window sensors & motion detectors with dial feature thank you!

Answer
the simplest one is the G.E. Simon XT. It is a wireless, self-contained, user-friendly alarm system that dials out and is, in my opinion, the easiest one for a regular person with no alarm technician experience, to program.

Powered by Yahoo! Answers