Paramagnetic (Dumbbell) Oxygen Analyser


Robust analyser for safe and hazardous areas, suitable for Oxygen enriched samples.

 Paramagnetic P8863 Oxygen analyzer allows the selective analysis of the O2 concentration in process gases taking advantage of its evident paramagnetic property that makes it attracted by a magnetic field.

 The specific features of the measuring principle makes the analyser virtually free from cross sensitivity by other gases, allowing its use in a variety of applications that range from purity measurement to O2 analysis in complex stream gases containing Hydrogen, Hydrocarbons and many others.

Measureable Gas

Oxygen [O2]

Main Features


High Performances

  • Free from cross sensitivity by other gases in the sample
  • Sensing unit temperature controlled
  • Insensitive to ambient temperature variations
  • Available as 4-20 mA transmitter or combined with a powerful microprocessor-based control unit


Easy Maintenance

  • Modular construction
  • Fast access to the inner PCB just unscrewing the housing cap
  • Possibility to remove the entire sensing unit from the housing just by unscrewing 2 screws and leaving her housing connected to the sampling system.


European Compliance

  • Low Voltage Directive 2014/35/EU
  • EMC Directive 2014/30/EU
  • Directive ATEX 2014/34/EU (optional)



ATEX certification for Zone 1 / Zone 21 with protection mode:

II 2 G D     Ex db IIC T6 Gb

                  Ex tb IIIC T85°C Db



ATEX Certificate Number CESI 03 ATEX 130


AccuracyGeneral accuracy: ± 1% of span (output signal).
Repeatability± 0.3% of span (short term).
Reproducibility24 hours: ± 1% of span.
LinearityBetter than ± 1% of full scale
Response TimeInitial: < 1 sec.; 90% of step-change: < 3 sec.
(with max. 1000 cc/min. flow rate)
DriftZero: max. ± 1% of span per week
Span: max ± 1% of span per week (without autocalibration)
Ambient Temp. Influence± 0.002% O2 per °C or ± 0.02% of span per °C
(-10°C ÷ +50°C)(whichever is greater)
Atm. Pressure Influence± 0.1 % of reading per hPa
Flow Rate Influence< 0.5% of span over flow range of 100 to 1000 cc/min.
Line Voltage Influencemax. 0.02% of span, for each 1% change of voltage.
Sample RequirementsFlow Rate: 250 ÷ 1000 cc/min.
Pressure: 3000 Pa minimum (with filter and flow meter).
RangeRefer to ordering information
Output4-20 mA proportional to ordered range on max. load of 250 Ω (or 125 Ω is galvanically insulation module is used)
Relative Humidity90% maximum.
Operation Temperature-10 ÷ +50°C (14 to 122 °F).
Temperature controlledat 50°C
Storage Temperature+70°C (158 °F) max.
Power Requirements24 Vac ± 10%, 50 VA from dedicated power supplier.
Pneumatic Connections¼” or 6 mm OD tubing (compression fittings supplied)
Wiring ConnectionsGeneral purpose: 2 openings for G 3/8" (PG 13 cable grip).
Ex-Proof: 2 openings for GK 1/2" (cable grip or conduit).



Oxygen purity measurements

Air separation plants

Oxygen measurements in Hydrogen stream

Inerting Control

Power Plants

Biogas & Landfill Gas

Steel & Metal Processing

Combustion gas

Sampling System


Due to the presence of delicate and optical parts inside the dumbbell cell, the P8863 needs an external sampling system able to deliver a perfectly clean and dry sample gas to the analyser at the proper temperature, pressure and flow rate.

ADEV has a wide experience in process and can provide the P8863 analyser combined with a sample and condition system designed for the specific application requirements. Contact ADEV for details.

Measuring Principle


Paramagnetic P8863 Oxygen analyzer allows the selective analysis of the O2 concentration in process gases taking advantage of its evident paramagnetic property that makes it attracted by a magnetic field. 

The Cell Block assembly is made of stainless steel and contains the cell cavity and pole pieces which produce two powerful magnetic fields in the cavity.

The magneto-dynamic cell consists of two nitrogen-filled quartz spheres arranged in the form of a dumb-bell. A single turn coil of platinum wire is placed around the dumb-bell which is suspended in a symmetrical non-uniform magnetic field. At its center, the dumb-bell bears a small mirror.

 When the surrounding gas contains Oxygen the spheres are pushed out of the magnetic field caused by the         relatively strong Para magnetism of Oxygen. The force on the dumb-bell is corrected by a current through the coil which is controlled by a photo-detection system via a light beam and the mirror on the dumb-bell.

 The feedback current, required to compensate the torque acting on the dumb-bell will be proportional to the Oxygen concentration in the gas sample through the cell.