Tunable diode laser absorption spectroscopy (TDLAS) is recognized as being the most effective technology for measuring trace moisture in a natural gas stream. It requires passing a state-of-the-art laser through the sample gas and measuring the amount of light absorbed by the water molecules at a specific wavelength before the laser strikes the photo-diode detector. Unlike other measurement technologies on the market, AMI’s innovative approach has significant advantages that make it the premiere choice for the Natural Gas Industry.

Among these advantages are:

  • Our TDL measurements respond with 90% full-scale in less than 2 seconds in both upscale and downscale, even after an ‘upset’ condition
  • Our Barracuda MODEL 4010BR TDL Moisture Analyzer is very stable over temperature, pressure and ‘upset conditions’ and does not require calibration
  • Our TDL Analyzer or Spectrometer can withstand the harsh, corrosive elements in the natural gas stream because it contains a breakthrough, highly-engineered sample system as part of its design

Natural gas companies have chosen TDL to measure trace moisture levels because the measurement technology responds very rapidly in ‘up & down scale’. However, though TDL-moisture spectrometers have been on the market for years, competitive designs lack many features and options that would enhance ease-of-use or improve the customer experience as part of their standard options package. Additionally, customers feel that the price of these TDL Moisture Analyzers is not often economically viable for their application.

For the past 20 years, Advanced Micro Instruments (AMI) has provided the Natural Gas Industry with the most innovative and effective solutions for trace oxygen analysis, and our company will now redefine the perfect solution for customers wanting to perform Trace Moisture Analysis with the introduction of the Barracuda MODEL 4010BR. Our new unit contains advanced innovations that optimize the moisture measuring capabilities of TDL and significantly bolsters the user experience.

Liquid Eliminator Cell Block™

This represents the next generation of Cell Block Technology, developed by AMI. Our patent-pending, compact, complete sample system approach virtually eliminates all potential leak paths while optimizing flow efficiency and response times. The volume and distance that the gas travels prior to entering the laser chamber have been drastically reduced. This is achieved by integrating all sample handling components as well as the Herriott Cell into a series of solid, compact blocks with machined, intersecting passages in place of long lengths of tubing and ‘off-the-shelf’ components, including the flow meter, metering valves and liquid-separation accessories. The Liquid Eliminator Cell Block™ features internal Liquid Separator Technology™. Using a unique liquid rejection membrane sealed between blocks, liquids are effectively removed and exhausted without ever reaching the critical laser optics.

Measurement Algorithm and Smart Calibration™

The Barracuda MODEL 4010BR is programmed with a proprietary measurement algorithm to carry out trace moisture measurements. Not only will the Barracuda MODEL 4010BR complete multiple scans every second for the signature H2O peak and CH4 (methane) peak, its algorithm contains a compensation function to account for pressure and temperature. This ensures maximum stability and accuracy regardless of the methane levels at the location where the measurement is taking place.

A Smart Calibration™ feature is also enabled on the Barracuda MODEL 4010BR. Over time, laser-based Moisture Analyzers eventually see gradual movement of their signature peaks on the x-axis of the measurement waveform. Any shift beyond the specific wavelength targeted by the spectrometer can impair the accuracy and reliability of the readings. In contrast to competitive TDL Moisture Analyzers that require taking the unit offline to ‘tune the spectrometer’ to reset the positions of the peaks, the Barracuda MODEL 4010BR can easily re-align the laser to the critical H2O peak and CH4 peak through the touch of a button.

Command Center Electronics Platform™

Like other advanced AMI gas analyzers, the Barracuda MODEL 4010BR comes with our state-of-the-art Command Center Electronics Platform™. This powerful Platform provides advanced functions and capabilities not available as standard options on other competitive devices, including:

  • 2 Fully Adjustable & Programmable Alarm Contacts
  • Datalogger from Moisture Readings, brownouts, calibrations, and power failures
  • 1 – 5 VDC and 4 – 20 mA isolated analog outputs
  • USB virtual comport and Modbus bi-directional RS485 communication to interface with advanced features

The entire platform comes as a standard option for our customers.

AMI sets a very high bar for every Barracuda MODEL 4010BR that ships from our facility. Each unit is individually tested in a special temperature chamber over its full temperature range from 20°F to 120°F and full pressure range from 700 – 1100 mbara for 12 straight hours to verify response time, noise, linearity and diurnal performance. The entire battery of tests is then repeated to ensure that the quality of every TDL Moisture Analyzer passes NIST standards and our own stringent internal test standards.

Moving natural gas through the pipeline requires the involvement of many key infrastructure players, including Production, Gathering, Compression, Gas Treatments and Transportation. Because corrosive gases and liquids reside in the gas stream, gas companies have established contractual agreements among themselves to regulate safe and effective custody-transfers. Tariffs are imposed if those components fall outside set parameters. Therefore, it is imperative to have accurate and reliable trace measurements, such as moisture, at custody-transfer sites because disagreements can lead to unexpected shut-ins, causing substantial losses and down time.

The release of the Barracuda MODEL 4010BR will set a new standard for TDL Trace Moisture measurements. Customers will quickly learn that the Barracuda MODEL 4010BR is PERFECTLY PRICED and will make it their Moisture Analyzer of choice.

Measurement Range
Minimum Detection Limit
Principle of Measurement

Area Classification

- compact, built-in sample system & Herriott Cell

Command Center Electronics Platform™

  • 2 Fully Adjustable & Programmable Alarm Contacts
    (delays & bypass w/ relay contacts)
  • USB Virtual COMport, Modbus bi-directional RS485 communication
  • Data Logger (moisture readings, temperature & power supply voltage)

Compact Size

Operating Temperature Range

Sample Cell Pressure Range

Inlet Gas Pressure

Recommended Flow Rate



Output - Isolated 1-5V or 4-20mA (user-selectable)


Permanent Mount
0.25 - 20.0 lbs of H2O
  • 0.25 lbs of H2O
  • Tunable Diode Laser Absorption Spectroscopy (TDLAS)
  • ±1% of Range or ±0.25 lbs of H2O, whichever is greater

Designed to meet requirements for Class 1, Div 1,
Groups B,C,D in a flammable gas ample

14.0"W x 9.5"H x 5.0"D

20°F to 120°F

700 to 1100 mbara

1.0 to 20.0 psig

1.0 to 2.0 SCFH

17 lbs

Choice of 10-28 VDC or 115VAC;
< 250mA @ 12VDC