HELP & QUOTE  |  651-407-9582

Bifurcated Fiber Optic O2 Sensors with Replaceable Cap


These probes are designed to have replaceable caps for periodic replacement.  The probes can be configured with or without a thermister.  In applications with changing temperatures a thermister configuration is recommended.  The replaceable caps are ideal in applications where the probe (fiber-thermister) are part of the sensing fixture (e.g., a Swagelock assembly).  Thereby this makes periodic maintenance simple by replacing only the cap.  The price for the caps includes a factory calibration which improves accuracy and replacement time.

Zero drift O2/DO sensor, 1000/2000 micron polymer fiber, 7" long, SS, 55 bar pressure rating. Thermistor length is 5'. Longer length thermistor of 10', 20', and 30' are available. Price include factory calibration.

High performance oxygen sensor. Dip probes with embedded thermistor with 0.375" OD and (W, BA, BMS, no) protective coating. 


W -- white acrylic overcoat
BA -- black acrylic overcoat
BMS -- black Medical Silicone overcoat


Hydrocarbon resistant oxygen sensor replaceable screw caps with (0.25", 0.375") OD and (W, BA, BMS, no) protective coating. There are two types of cap coatings. 

1) The HIPOXY (formerly AP) series designed for zero long term drift with applications:

Environmental monitoring
Process control
In line monitoring in beverage industry
Waste water treatment
Long-term measurement in soil

2) The HYROXY (formerly HCR) series for Hydrocarbon Resistant Oxygen applications:

Oil industry: refineries, fuel processing
Chemical industry involving explosive hydrocarbons and flammable solvents
Aviation industry: OBIGS, OBOGS, online real-time fuel tank monitoring

New part number -- Old part number


HIPOXY-SC-375 -- FMI-AP-OX-375-cap


HYROXY-SC-375 -- FMI-HCR-OX-375-cap

AP formulation

HCR formulation

Response rate

T90 = 3 seconds

T90 = 1 second

Dynamic range in gas

0-100% O2/0-760 mmHg O2

0-100% O2/0-760 mmHg O2

Dynamic range in water (DO)

0-40 ppm (wt)

0-40 ppm (wt)

Resolution in gas

0.005% O2 / 0.04 mmHg

0.05% O2 / 0.4 mmHg

Resolution in water (DO)

0.002 ppm (wt) / 2.0 ppb (wt)

0.02 ppm (wt) / 20 ppb (wt)


5% of reading

5% of reading

Lowest detectable level (gas)

0.005% O2 / 0.04 mmHg

0.05 % O2 / 0.4 mmHg

Lowest detectable level (water)

0.002 ppm (wt) / 2.0 ppb (wt)

0.02 ppm (wt) / 20 ppb (wt)

Sensor drift

Zero drift long term continuous operation

0.0001 O2% per hour

Operating temperature

-50 to + 100 C

-50 to + 200 C

Probe lifetime

3 years

3 years