Dakota Digital MMX-6 operation manual Transducer Selection

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Dakota Ultrasonics

TRANSDUCER SELECTION

The MMX-6 DL is inherently capable of performing measurements on a wide range of materials, from various metals to glass and plastics. Different types of material, however, will require the use of different transducers. Choosing the correct transducer for a job is critical to being able to easily perform accurate and reliable measurements. The following paragraphs highlight the important properties of transducers, which should be considered when selecting a transducer for a specific job.

Generally speaking, the best transducer for a job is one that sends sufficient ultrasonic energy into the material being measured such that a strong, stable echo is received by the MMX-6 DL. Several factors affect the strength of ultrasound as it travels. These are outlined below:

•Initial Signal Strength

The stronger a signal is to begin with, the stronger its return echo will be. Initial signal strength is largely a factor of the size of the ultrasound emitter in the transducer. A large emitting area will send more energy into the material being measured than a small emitting area. Thus, a so-called "1/2-inch" transducer will emit a stronger signal than a "1/4-inch" transducer.

•Absorption and Scattering

As ultrasound travels through any material, it is partly absorbed. If the material through which the sound travels has any grain structure, the sound waves will experience scattering. Both of these effects

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Contents Dakota Ultrasonics Dakota Ultrasonics Contents Disclaimer Very Important Introduction Blank Operation KeypadDakota Ultrasonics MMX-6 DL Ultrasonic Thickness Gauge Dakota Ultrasonics Display Dakota Ultrasonics Is currently operating in echo-echo Thru-paint/coating mode Transducer Making Measurements Dakota Ultrasonics Condition and Preparation of Surfaces Probe Zero Performing a Probe-ZeroCalibration Dakota Ultrasonics Calibration to a known thickness Dakota Ultrasonics Calibration to a known velocity Dakota Ultrasonics Two Point Calibration MMX-6 DL Modes Changing Units in / MM Units in/mmBack light Using The Back LightScan Mode Using Scan Mode Alarm ModeUsing the Beeper Dual-Multi Mode Connecting To a Computer RS232 Serial Port & The Data LoggerUsing The Data Logger Using the Data Logger Clearing a Storage Location Clearing an Entire File Clearing all Files Sending All Files to a ComputerPrinting a File Transducer Selection MMX-6 DL Ultrasonic Thickness Gauge Dakota Ultrasonics Blank Appendix a Product Specifications PhysicalPower Source KeypadMeasuring hot surfaces Appendix BApplication Notes Measuring pipe and tubing Measuring laminated materials Measuring Through Paint & Coatings Blank Appendix C Sound Velocities of some Common MaterialsBlank Warranty Information Warranty Statement
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