CO% Range Gas Analyzer: GPro 500

CO% Range Gas Analyzer: GPro 500

Tunable Diode Laser for CO% Measurement

The GPro 500 carbon monoxide percent gas analyzer is a unique tunable diode laser spectrometer designed for measurement of CO in a gas stream at high temperatures. It uses a folded-path laser beam design for simple installation and CO% measurement.

Top Performance in CO% Measurement
A CO% analyzer for challenging applications, the GPro 500 provides reliable measurement in FCC units, PTA, steam reforming, and hydrogen production.

Low Maintenance and Operating Costs
This CO% gas analyzer is designed to operate at high temperatures, in situ without a conditioning system, reducing the total cost of ownership.

Easy Installation
The GPro 500 is an alignment-free TDL gas analyzer, meaning that the typical challenges of TDL installation and alignment are significantly reduced.

CO% Range Gas Analyzer: GPro 500

TDLCO Gas Analyzer Frequently Asked Questions

Why use a TDL sensor for measuring carbon monoxide?

TDLs have many advantages over other carbon monoxide measurement technologies...

Why use a TDL sensor for measuring carbon monoxide?

TDLs have many advantages over other carbon monoxide measurement technologies. Firstly, they are installed in situ in the process pipe or vessel so are exposed directly to the gas and therefore measure immediately. Some other analyzers measure a sample of gas that has been extracted and conditioned, which takes time and increases risk. Secondly, TDLs are immune to the presence of other gases in the process and will only measure CO. Thirdly, they are extremely reliable and require practically zero maintenance.


How can a CO TDL reduce costs?

Unlike other gas measurement technologies, TDLs have a very low maintenance requirement. Once installed, they will run reliably for many months without needing any maintenance. When used in combustion processes they can ensure the fuel/air mixture is exactly right and can reduce fuel costs by thousands of dollars. For more information check our Payback Calculator.


Are TDLCO sensors easy to install?
Sometimes. Once the insertion point has been selected it’s a matter of fitting one or two flanges and a temperature and pressure sensor. Most TDLs are of a cross-stack design, meaning that they’re comprised of two parts (laser source and receiver) that sit opposite each other in the pipe or vessel. The two units have to be very carefully aligned which can be problematic. The GPro 500 has both parts installed in the same unit. The laser source is reflected by a three-sided mirror and is directed back to the receiver. Therefore, no alignment is required. Watch our video on easy installation.


In which applications can TDLs be used?

TDLs have a wide range of applications, including process control in direct chlorination and oxy-chlorination; safety monitoring in VCM waste gas recovery; and combustion optimization in package boilers, thermal oxidizers, fired heaters, FCC units, etc. For more information check our Application eBooklet


Specifications - CO% Range Gas Analyzer: GPro 500
Gas Measured Carbon monoxide (CO%)
Lower Detection Limit 1500 ppm-v
Measurement range 0-100%
Accuracy 2% of reading or 1500 ppm, whichever is greater
Linearity Better than 1%
Resolution 1500 ppm-v
Drift Negligible (<2% of measurement range between maintenance intervals)
Sampling rate 1 second
Response time (T90) CO in N₂ 300 ppm-v to 0% in <4 seconds
Repeatability ±0.25% of reading or 0.75-v CO (whichever is greater)
Process pressure range 0.8 bar - 1.5 bar (abs)/11.6 psi - 21.7 psi (abs)
Process temperature range 0-250 °C (23-482 °F); Optional (for probe installation) 0-600 °C (0-1112 °F) with additional thermal barrier
Effective path length 50 mm - 10 m, depending on adaption
Features and Benefits

Meets Critical Application Needs
This CO% analyzer is ideal for measurement and control applications in FCC units, styrene, syngas, and ammonia manufacturing. These TDL gas analyzers offer a precise, reliable and fast measurement in critical applications, and are SIL 2 compatible.
Flexible and Consistent Platform
Immediate, In Situ Measurement
The GPro 500 CO% gas analyzer is installed in situ, so you get a quick response without the need to extract and condition a sample. This offers a reliable and cost-effective alternative to technologies that require extraction and conditioning of gases.
Fast, Intuitive Navigation
Designed for Challenging Installations
The GPro 500 is configurable, enabling the carbon monoxide range spectrometer's measurement system to be paired with a variety of process adaptions to meet a wide range of installation requirements, including pipe diameters from 50 mm to over a meter.
Plug and Measure
Predictive Diagnostics Ensure Long Life
This CO% gas analyzer uses Intelligent Sensor Management (ISM) technology to offer predictive diagnostics on analyzer condition, including informing you when cleaning of the optical path will be required.
Easy Configuration



Gas Analytics Brochure
Safety, quality, productivity: that’s what’s most important to you. And that’s why our approach to designing analyzers and sensors is based around a s...


Gas Analysis
In this free booklet we discuss the theory of absorption spectroscopy and how TDL analyzers are being employed in an increasing number of process and...
Complimentary eBooklet: Gas Applications for GPro 500 Analyzers
This eBooklet is intended as a convenient reference to a selection of the most common GPro 500 applications.

White papers

White Paper: TDLs for All Your Processes – Folded-Path Gas Analyzers
Our portfolio of folded-path tunable diode laser (TDL) gas analyzers now has a unique range of process adaptions. Combined, they have opened the door...
No More Purge Gas-New TDLs for Combustion Processes
This white paper explains how the new generation of TDLs not only offers exceptional fuel costs savings, but eliminates the need for process side purg...
Measurement of Oxygen Concentration
Gaseous oxygen measurement with amperometric sensors is the most direct and easiest solution for protection against oxidation and explosion.
Inerting Made Efficient, Replacing Extractive Oxygen Analyzers
Manufacturing operations must keep output and quality their top priority. Switching from maintenance-intensive on-line extractive systems to a more re...
Measurement of Oxygen Concentration
Gaseous oxygen measurement with amperometric sensors is the most direct and easiest solution for protection against oxidation and explosion.
Polarographic Oxygen Measurement
For the measurement of oxygen in continuous process analysis, several technologies are available.
Minimizing Inerting System Maintenance
This white paper explains how TDL O₂ sensor can minimize inerting system maintenance & how to integrate them into a DCS system for fully automated oxy...
Gas Analysis Made Easy
Tunable Diode Laser (TDL) oxygen sensors from METTLER TOLEDO unite the best elements of two technologies to form a highly dependable monitoring system...

Technical Specifications


Safety Manual for TDLS GPro 500 - Tunable Diode Laser Spectrometer
This document contains information and safety instructions required to use the GPro 500 with direct analog output option in SIL environments.
Get Your Quote
CO% Range Gas Analyzer: GPro 500
USP Class VI


Get Your Quote
CO% Range Gas Analyzer: GPro 500
USP Class VI
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