Original Alphasense O2-A2 O2-A3 Battery-Powered Oxygen Sensor

Specifications
Brand: Alphasense
Model: O2-A2 O2-A3
Made in: UK

O2-A2
Measurement Range: 0–30% Vol O₂
Sensitivity: 80–120 μA @ 20.9% O₂ (air)
T90 Response Time: <15s (20.9% → 0%)
Zero Current (Nitrogen): <2.5 μA
Lifespan: ≥24 months (2 years in 20.9% O₂ environment)
Recommended Load Resistor: 47–100 Ω
Power Supply: Zero bias, no external voltage needed, ready to measure without warm-up
Operating Temperature: -30℃ ~ 55℃
Humidity: 5–95% RH (non-condensing; short-term max 99% RH)
Pressure: 80–120 kPa
Dimensions: Ø20.0 mm, Height 17.4 mm (including foam gasket)
Pins: 2-pin

O2-A3
Measurement Range: 0–30% Vol O₂
Sensitivity: 55–85 μA @ 22℃, 20.9% O₂ (air)
T90 Response Time: <15 s (20.9% → 0% O₂, 47Ω load)
Zero Current (Nitrogen): <2.5 μA
Lifespan: ≥36 months (3 years in air, output drops to 85% of initial)
Recommended Load Resistor: 47–100 Ω
Power Supply: Zero bias, no external voltage needed
Operating Temperature: -30℃ ~ 55℃
Humidity: 5–95% RH (non-condensing; short-term max 99% RH)
Pressure: 80–120 kPa
Dimensions: Ø20.3 mm, Height 16.8 mm (including foam gasket)
Pins: 2-pin

-25%