Used to measure oxygen (O2), Coulometric sensing is based on a simple, non-depleting process that responds quickly to changing O2 levels. The heart of our DF-500 range of oxygen sensors, it delivers the low-level detection that is essential for UHP gas applications.
Our Coulometric technology enables the measurement of O2 at percent or parts-per-million (ppm) levels. It is non-depleting, so there is no requirement for periodic cell replacement and it avoids the false low readings associated with standard electrochemical sensors.
It operates through a simple Coulometric process where O2 from the sample gas is reduced to hydroxyl ions at the sensor cathode.
The resulting current flow is proportional to the O2 content in the gas, and the process signal can be displayed in ppm or parts-per-billion (ppb) units of O2.
Coulometric sensors respond very quickly to changing O2 concentrations. For instance, a 0-1,000ppm range sensor can be exposed to air and in less than a minute will measure <10ppm on pure nitrogen. This is highly beneficial for users who have upset-prone applications.
Additionally, the performance of the sensor is unaffected by reasonable changes in flow rate.
Because the non-depleting sensor is not consumed when exposed to O2, it has a long lifespan and does not require a purge gas to protect it when not in use.
Coulometric sensing works alongside Laser Moisture technology in our DF-760E and DF-760E ULTRA analyzers, for a highly sensitive dual measurement of oxygen and moisture at ppm levels. Coulometric sensors should avoid sample streams that contain acidic gases. For applications involving these gases, a Paramagnetic or TDL sensor is recommended instead.
Solder reflow ovens
Reactor process control
Industry-leading lower detection limits
Fast response and rapid recovery
Non-depleting sensor with a long lifespan
Sensitive, parts-per-million measurements of O2, for example in impurity monitoring for UHP semiconductor gases
Learn more about all our gas analyzer solutions that use this sensor technology.
The 4900 Multigas is a high-performance CEMS analyzer designed for a wide range of multi-gas measurements.
A rugged ultra-thin film Aluminum Oxide moisture sensor which measures moisture in a wide variety of gas phase process applications.
Built specifically to work in harmony with the AquaXact 1688 ultra-thin film Aluminum Oxide moisture transmitter.
The Chroma is optimized to specific background gases to ensure optimum performance for your application.
An ultra-trace Coulometric oxygen analyzer, the DF-550E is optimized for quality measurements in ultra-high-purity electronic gases.
The DF-560E provides the semiconductor industry with industry-best oxygen (O2) measurements for quality control in ultra-high-purity (UHP) electronic grade gas.
A superior quality control solution for ultra-high-purity (UHP) electronic grade gases, the DF-560E Ultra delivers an industry-best detection of 45 parts per trillion for oxygen (O2).
The DF-730 is an ultra-trace moisture analyzer that monitors the electronics-grade, high-purity hydrogen chloride (HCl) gas used in semiconductor fabs.
A trace moisture analyzer using Tunable Diode Laser (TDL) sensing technology, the DF-740 is designed to measure contaminants in UHP-grade ammonia.
The DF-745 delivers trace and ultra-trace measurements of moisture for ultra-high-purity (UHP) electronic gas checks in LED/LCD manufacturing processes.
The DF-745 SGMax is designed for the measurement of diverse gas mixtures in specialty gas blending applications.
The DF-750 is a trace/ultra-trace moisture analyzer optimized for measurements in the ultra-high-purity (UHP) gases used in 300mm semiconductor fabs.
Delivering industry-leading trace/ultra-trace moisture measurements, the DF-750 ULTRA is optimized for quality monitoring in the ultra-high-purity (UHP) gases used in 300mm semiconductor fabs.
Designed for quality control applications in UHP bulk gases, the compact DF-760E analyzer is a unique solution for the dual measurement of trace and ultra-trace moisture
Designed for industry-leading quality control measurements in UHP bulk gases, the compact DF-760E ULTRA is a unique dual-analysis solution for trace and ultra-trace moisture and oxygen.
With trace analysis capability, the FID is ideal for ASU safety and quality control applications.
Designed to measure O2 and COe in flue gases for improved combustion efficiency and reduced emissions.
A solid-state, non-consumable sensor configured to operate in process gas streams. Provides a direct hydrogen measurement that is not cross-sensitive to other gases.
Utilizes an internally heated oven set to 190°C (374°F) to maintain the sample gas above its dew point, for optimum performance in total hydrocarbon analysis (THC).
Unmatched installation flexibility plus cost and performance benefits, ready for fast, accurate and responsive measurements in combustion and process control.
Compact, high-performance Tunable Diode Laser (TDL) analyzer, specifically optimized for ammonia slip measurement
Optimized for the fast, accurate and responsive measurement of process oxygen (O2) in hot or hazardous conditions.
Designed for the measurement of oxygen (O2) in potentially flammable gas samples. Certified to Zone 0 and Zone 1 and suitable for measuring percent levels of O2.
A small sample volume portable benchtop analyzer focused on the checking and quality control of gas mixtures in Modified Atmosphere Packaging (MAP).
The MiniHD 5200 portable gas analyzer is a rugged, heavy duty analyzer designed to accurately measure the levels of O2, CO and CO2 within common gas mixtures.
The only truly portable battery-powered gas analyzer with MCERTS and TUV certification, offers single or dual measurement of oxygen (O2) and carbon dioxide (CO2).
The MonoExact DF150E combines the reliability of Servomex’s tried and tested Coulometric oxygen sensor with a more user-friendly package.
Designed specifically for accurate measurements of oxygen in industrial gas (IG) applications.
A high-performance multi-gas analyzer designed to provide up to four simultaneous gas stream measurements.
The MultiExact 4200 analyzes up to four gases simultaneously for Syngas and HyCO
Incorporating the latest advances in gas sensing and signal processing methodology, the NanoChrome revolutionizes ultra-trace purity measurements.
Using proven ultra-trace sensing, the NanoChrome ULTRA conquers the most stringent demands of the semiconductor industry, delivering a cost-effective solution compared to competing technologies.
Measures NO or NO/NO2/NOx concentrations in industrial gas and vehicle emission applications.
Designed to reliably measure up to 100% oxygen (O2) in many industrial applications, the Oxy 1800 is a stable, accurate O2 analyzer for safe area use.
The Oxy 1900 oxygen (O2) gas analyzer sets new standards of flexibility, stability and reliability from a single, cost-effective unit.
A life safety monitor designed for safe area or hazardous area environments, the OxyDetect delivers the superior performance of non-depleting Paramagnetic O2 sensing technology.
The high-specification OxyExact 2200 O2 analyzer offers an unrivaled combination of precision, flexibility and performance for optimum process and safety control.
The Plasma delivers an accurate, highly stable and reliable measurement, with high sensitivity in the 0-1ppm range.
A getter-based purification unit designed for the purification of carrier gases used in Gas Chromatography (GC) and other analytical applications
Flexible single and multicomponent gas analysis capability for corrosive, toxic and flammable sample streams.
A real-time optical analyzer utilizing the Precisive field-proven optical bench. A breakthrough capability in the continuous analysis of light hydrocarbons C1-C6.
Get a free copy of our special Expert Solutions magazine focusing on our complete range of sensing technologies. It’s available to download now.
If you still need guidance to find the best solution for your process, we’re here to help. Our expert team combines applications knowledge with extensive experience and deep understanding of the sensing technologies available. We’ll help you find the solution that meets your unique needs.