AlphaSense O2-A3 Oxygen Sensor

AlphaSense O2-A3 Oxygen Sensor
Regular price $82.00 USD Sale price

Compare at $69.00 USD

POs or wholesale quantity discounts click here

The AlphaSense O2-A3 oxygen sensor is a plug-in replacement sensor for hand-held gas detectors that use an O2-A3 sensor. 

Verify the sensor you are replacing has AlphaSense O2-A3 printed on the side before ordering. Due to our low prices we cannot accept returns for the wrong sensor.


  • 0.1 to 20.9% oxygen sensor
  • Does not require calibration
  • Up to 3 year lifespan
  • Small, compact and maintenance free
  • Measurement Range: 0.1-20.9% Oxygen
  • Output @ 20.9% Oxygen: 60-85 uA
  • Output @ 0% O2: < 2.5 uA
  • Response Time: < 15 sec. t90 (s) from 20.9% to 0%
  • Linearity: 0.6% O2 deviation @ 10%
  • Output drift: < 1% change @ 3 months
  • Operating life: > 36 months until 85% original Output of 20.9%


  • Dimensions (sensor): 17.4mm x 20.3mm


Sensor Pin Sockets - Manufacturers do not recommend soldering to the pins. Pin sockets can be purchased from Andon distributors. Click here to search for your sensor's socket. Select the brand PDF, find your sensor, then search for the Andon part number for your sensor's socket.

Customer Reviews

Based on 8 reviews
Claudio Vilas Boas Favero
Great sensors, quick delivery

Great sensors, quick delivery

john hernandez

compliance and punctuality

Ken Sadogierski
worked good

Plugged in and worked with out a problem.
Make sure you get the exact same thing.

Sandy McLardy
replaced my bacharach o2

i own the bacharach fyrite intech combustion analyzer and this o2 sensor fit like a glove. after rebooting it self calibrated and works great.

Brandon Slabach
Great service

Great service, great website, great timely shipment and arrival. Very happy with the order.

"Swift response and shipment. The product is easy to setup and use. It is just what I was looking for."

- Shima Tomohiro

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