Trace oxygen detection as low as 50 ppt


  • Gas Quality Control
  • Gaseous CRMs & Calibration Gas Mixtures
  • High-Purity Gases & Systems
  • Hydrogen Fuel Cells
  • Research & Development
Detection and Matrix Range LDL (3σ) Precision (1σ) @ zero
O2 in He0 – 0.5 ppm50 ppt17 ppt
O2 in Ar0 – 1 ppm90 ppt30 ppt
O2 in H20 – 2 ppm150 ppt50 ppt
O2 in N20 – 2.5 ppm200 ppt70 ppt
O2 in CO2§0 – 5 ppm5000 ppt300 ppt
§Special configuration required,
must be specified at time of order.
Operating range See Detection Capability table
Detection limit (LDL, 3σ/24h) See Detection Capability table
Sensitivity (3σ) See Detection Capability table
Precision (1σ, greater of) ± 0.75% or 1/3 of Sensitivity
Accuracy (greater of) ± 4% or 1/2 of LDL
Speed of response < 3 minutes to 95%
Environmental conditions 10°C to 40°C, 30% to 80% RH (non-condensing)
Storage temperature -10°C to 50°C
Gas Handling System and Conditions
Wetted materials 316L stainless steel, 10 Ra surface finish
Leak tested to 1 x 10-9 mbar l / sec
Gas connections 1/4” male VCR inlet and outlet
Sample inlet pressure 10 − 125 psig (1.7 − 9.6 bara)
Sample flow rate 0.5 – 1.8 slpm (gas dependent)
Sample gases Most inert matrices
Gas temperature Up to 60°C
H2 supply requirements* ~15 sccm, 20 − 125 psig
Dimensions, H x W x D
Standard sensor 8.73" x 19.0" x 23.6" (222 mm x 483 mm x 599 mm)
Standard sensor 45 lbs (20.4 kg)
Alarm indicators 2 user programmable, 1 system fault, Form C relays
Power requirements 100 − 240 VAC, 50/60 Hz
Power consumption 450 Watts max.
Signal output Isolated 4−20 mA
User interfaces 5.7” LCD touchscreen, 10/100 Base-T Ethernet, RS-232
  802.11g Wireless (optional), Modbus TCP (optional)
Certification CE Mark
U.S. Patent #7,277,177 • U.S. Patent # 7,255,836  
*H2 supply (maximum 10 ppm H2O and O2
impurity) is required for sample conditioning
via catalytic conversion.
For enhanced safety, a mixture of 3% H2/97% N2
can be used as an alternative to pure H2.
LDL is dependent upon the quality of the sample
gas and the integrity of the sampling system.
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