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Operating Temperature Question

  1. Apr 1, 2014 #1
    I am working at determining how much carbon monoxide is present in the smoke of an industrial rotisserie smoker for BBQ. I have sensorsfrom Applied Sensor called AS-MLC CO sensors. The problem is that their operating temperature is 270 degrees celsius (around 500 degrees F). The sensors can't sit right in the smoke to get that hot because I am sure it will get easily get clogged from the soot and such. I want the sensors to be located within the smoker itself, but there it would only get to around 250 degrees F.
    Do you agree that the sensor would get clogged when placed right near the wood where the smoke is coming off of?
    Also, one solution I considered to heat the device that much is by connecting a toaster oven heating element to it that is constantly running at the heat I need it to be at. The element would be contained in a container, and a fan would blow the hot air through a tube to the sensor. Would this work?
    I have included a link to the datasheet: https://www.appliedsensor.com/pdfs/AS-MLC_CO.pdf

    My last question is that one the pins for the sensor on the datasheet it says that there is a pin for heater power and a pin for heater ground. Would it still work if I connected the sensor to a power supply, but heated it separately by blowing the air onto it?

    Thanks for the help in advance!
  2. jcsd
  3. Apr 1, 2014 #2


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    The datasheet says the Ambient temperature range is for -40°C to 50°C (lower than op. temp.).
  4. Apr 1, 2014 #3
    Okay, so if I understand correctly, the ambient temperature is the temperature of the air surrounding the sensor, and the operating temperature is the temperature range it can operate within, correct?
  5. Apr 1, 2014 #4


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    There is a CO level transducer (gas analyser) in motor car exhaust systems, I believe. That is a pretty savage environment. Perhaps you could approach the problem from that direction.
    Also, the idea of a bypass channel with filtering before the sensor has merit if there is to be lots of smoke and oil vapours about.

    Afaik, the heater inside the device is there to ensure the cell is operating at above ambient temperature - possibly to ensure that the cell boils off its products. That would imply, I think, that it needs a heater supply.
    Last edited: Apr 1, 2014
  6. Apr 1, 2014 #5


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    It has an internal heater:

    Pin Function
    1 Sensor electrode 1
    2 Heater power
    3 Sensor electrode 2
    4 Heater ground
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