Technical Articles: Tech Tips, Application Notes, White Papers

Tech Tips – Basic and Advanced Data Acquisition Topics

Using ULx for NI LabVIEW Part 1 – Learn How to Acquire One Sample of Data
It’s easy to use NI LabVIEW with MCC hardware. This three part tech tip explains the steps needed to measure analog signals, manipulate data, and control digital I/O.

Using ULx for NI LabVIEW Part 2 – Learn How to Acquire and Display Data to a Chart and Save Data to a File
This tech tip explains how to acquire data at a steady rate, display the data in a strip chart, save the data to a log file, and notify the operator if is there is an error.

Using ULx for NI LabVIEW Part 3 – Learn How to Scale Data and Add Alarming and Digital Control
The final tech tip in this series explains how to add scaling, alarming, and digital control to a VI.

How to Measure Thermocouples using a DAQ Device
Thermocouples are a popular and inexpensive way to measure temperature. Learn about the needed signal conditioning and CJC required to accurately measure thermocouples using a DAQ device.

Measuring 4-20 mA Current with MCC DAQ
The 4-20 mA current loop interface came about because of the need to transmit information over long distances. Learn how to measure 4-20 mA signals using an MCC DAQ device and a 250 ohm precision resistor.

Measuring Thermocouples with Raspberry Pi® and the MCC 134
This document explains the difficulties in making accurate thermocouple measurements, how the MCC 134 DAQ HAT accomplishes it, and how MCC 134 users can minimize measurement errors.

Raspberry Pi Data Acquisition using Universal Library for Linux
This document is intended for application developers familiar with MCC DAQ devices who are interested in acquiring data on a Linux platform using a Raspberry Pi.

Raspberry Pi Data Acquisition using MCC DAQ and Third-Party Linux Drivers
This document shows how to acquire data from an MCC DAQ device using a test application installed on a Raspberry Pi computer.

Utilizing Digital Inputs / Outputs with MCC DAQ
This document shows how to write to a single digital I/O bit using an MCC DAQ device and various software platforms.

Acquiring an Analog Waveform with MCC DAQ
This document shows how to capture an analog waveform using an MCC DAQ device and various software platforms.

Acquiring a Single Analog Input Value with MCC DAQ
This document shows how to read a single analog input value using an MCC DAQ device and various software platforms.

Basic Analog Input Signal Connections (Part 1)
This document provides a basic understanding of the following analog input signal connection concepts and practices: single-ended inputs, differential inputs, common mode voltage, common mode range, and system grounding and isolation.

Basic Analog Input Signal Connections (Part 2)
This document provides DAQ product users with recommended single-ended/differential wiring guidelines for analog input measurements after considering sensor grounding, DAQ system grounding and isolation, and common mode voltage.

Choosing a Software Environment for Data Acquisition
This document highlights the different Software options available for data acquisition (DAQ) applications, and outline the Measurement Computing Corporation (MCC) support for these options.

Digital I/O Techniques
This document provides an overview of the following digital I/O techniques used in the data acquisition (DAQ) industry, pull-up and pull-down resistors, TTL to solid state relays, voltage dividers, and low-pass filters.

Accuracy, Precision, Resolution, and Sensitivity
Instrument manufacturers usually supply specifications for their equipment that define its accuracy, precision, resolution and sensitivity. Unfortunately, not all of these specifications are uniform from one to another or expressed in the same terms.

MCC Application Notes

Wind Turbine Gearbox Fault Test System using WebDAQ 504
The WebDAQ 504 internet enabled data logger was used to develop an IIoT testing solution for collecting and analyzing vibration data from bearings and other components in wind turbine gearboxes.

AC Power Monitoring IoT Solution using MCC 118 with Raspberry Pi®
A mobile communications company used the MCC 118 to create an IoT solution to monitor and analyze the external city power being supplied to their facilities.

Probe Permeameter Machine using MCC 118 and MCC 134 with Raspberry Pi®
RO Scientific used the MCC 118 voltage measurement HAT and the MCC 134 thermocouple measurement HAT in the design of a probe permeameter machine used in testing rock samples for the oil and gas industry.

Machinery Monitoring and Predictive Maintenance using MCC 172 and MCC 134 with Raspberry Pi®
The MCC 172 IEPE measurement HAT and MCC 134 thermocouple measurement HAT are used to measure vibration and temperature respectively, and collect the data needed to create accurate measurements, analysis, and strategy.

Neuromuscular Biomechanics Test System Using MCC 172 and Raspberry Pi®
The Raspberry Pi and MCC 172 allowed researchers to create a lightweight and wearable DAQ solution to measure dynamic activity for testing neuromuscular biomechanics.

Portable Test System Using MCC DAQ and Raspberry Pi
Townsend Engineering Services, Inc. chose the USB-1608FS-Plus to design a system to be used for testing sports and playground surfaces.

Developing a Scattered Light Detection Instrument
OSI Optoelectronics selected the OEM-ready USB-2533 from Measurement Computing to provide 16-bit digitization and data transfer to a PC over the USB bus.

Acquiring Data Across Networks
The USB-7202 was selected by Veritium because of its hardware capabilities and the small footprint software framework which greatly simplified application development, making it ideal for OEM and embedded applications.

Test Instrumentation for Nuclear Power Plants
InHand Electronics was contracted to design and build the next generation of test instrumentation for nuclear power plants. The Measurement Computing USB-2533 using MCCs Windows® CE deployment platform stood out as providing the best solution.

Monitoring Theme Park and Amusement Rides
The LGR-5329 was chosen to monitor the rides because of its small footprint, flexible integration into over a dozen rides, optoisolation, and high-speed data capture that is provided at one tenth the cost of other commercially available loggers.

Optimizing Swimmers' Performance
Hector Engineering saved hours of development time creating the E-Rack interface with DASYLab’s intuitive graphical programming and library of modules.

Catapult Torsion Testing
MCC's USB-2404-UI data acquisition system monitors signals from load cells and strain gages on a championship pumpkin catapult.

DT Application Notes

Benefits and Pitfalls

Benefits and Potential Dangers of Using USB for Test and Measurement Applications
USB is one of the fastest growing standards within the computer and electronics industries today. But, beware – it also contains some potential dangers that can cause catastrophic results depending on your application. Galvanic isolation is the key to avoiding this danger.

Benefits of Simultaneous Data Acquisition
When choosing a data acquisition board, many different selection criteria are used. Speed, resolution, accuracy, and number of channels are all important considerations. For many applications, a simultaneous acquisition device is certainly the architecture of choice due to its inherent speed and accuracy.

Benefits of the PCI Bus for Data Acquisition
The PCI bus is a board-level expansion standard with important benefits to anyone whose work involves PC-based data acquisition or image processing. The high-bandwidth of the PCI bus allows simultaneous, real-time gathering of gap-free analog and digital input data, along with outputs for analog stimuli and digital control.

Benefits of the Universal Serial Bus (USB) for Data Acquisition
USB devices are external to the computer – there is no need to open up the computer to install them. This external location also provides performance benefits for noise-sensitive devices like data acquisition peripherals. In minutes, and with state-of-the-art accuracy, you're capturing data: temperature, pressure, or sound.

Data Acquisition: Gotchas for USB Measurements
USB provides test engineers with an inexpensive, easy-to-use, highs peed bus standard for PC-based test and measurement systems. The standard, however, does not mandate signal-circuit isolation. Isolation protects your PC from damage and preserves the integrity of the data by physically separating electrical connections between circuits, thereby eliminating potentially harmful voltage or current from flowing through your system.

DSP Data Acquisition

Real-Time DSP Data Acquisition for High-Speed Host Transfer
The architecture of a data acquisition system utilizing the processing capability of a DSP chip has existed for many years. The ability to do this in a local loop in real time is available today with chips such as the Texas Instrument floating-point TMS320C6713.

Subject-Oriented Software Development System for DSP
Data acquisition for real-time applications on a DSP board is an engineering challenge. Data Translation has resolved this dilemma by creating its own DSP subject-oriented software development system. This system lets users access sophisticated DSP algorithms from the standard Windows® world.

General Data Acquisition

Choosing Data Acquisition Boards and Software
Data acquisition boards help you measure real-world information represented by analog signals. The analog signals come from sensors or transducers that convert temperature, pressure, sound, vibration etc into voltage. The electronic sampling of analog signals is called A/D conversion or analog-to-digital conversion. A/D conversion changes real-world analog voltages into digital codes for computer processing and storage.

Data Acquisition Helps Veterinarians Assess Animal Gait Problems
To assess the effects of leg or hip injuries in horses and dogs and develop treatment, it is helpful to veterinarians to evaluate the gait patterns of the animals. Sharon Software, Inc. has developed software for a PC-based data acquisition system that is currently used for research and clinical service at sites throughout the United States and Canada.

Embedded Signal Processing System: Build or Buy?
Engineers confronting the need to add real-time signal processing capabilities to a product will consider the build-to-buy question.

Engine Monitoring and Testing with the DT9836
Engines are the driving force behind many forms of transportation and/or agricultural machinery. They are designed to run at high speeds and at high temperatures. They are stringently tested to perform under the harshest of conditions in order to satisfy very high quality standards. This testing process using data acquisition needs to be accurate, precise, repeatable, and most of all correct.

Gas Analyzer Simulation Using Measure Foundry
A worldwide producer of gas analyzer systems, wanted to test their analyzers without having to introduce real gas into the system. This would save time, money, and create a safer work environment.

Ground Penetrating Radar for Road Maintenance Using the DT9832
A road maintenance/ground penetration analysis company provides analysis and data recording of newly laid asphalt roads. The company presently does this with the use of about a half a dozen specially equipped RV's. They were looking to use a lower cost, high speed, portable data acquisition device which had the ability to keep up with the vehicle when driving at speeds up to 60mph while performing the radar pass over the newly laid asphalt.

High-Performance Data Acquisition on USB
A common belief among engineers is that to get the best performance, a PC based data acquisition module must plug into the PCI bus. Properly implemented, however, a data acquisition module can use the PC’s USB 2.0 port to pump data into a PC as fast as PCI-based cards. The keys to achieving this performance are a hardware USB interface on the module and optimized driver software for the host system.

Lightning Mapping System Bolsters Air Travel Safety
Researchers at the Langmuir Laboratory for Atmospheric Research at the New Mexico Institute of Mining and Technology have been getting a real charge out of their work. They have developed a system for mapping lightning that measures radiation to produce a three-dimensional map of lightning activity and it has been enhanced with Data Translation's DT301 PCI data acquisition board.

Mirrorcle Technologies Using the DT9812-10V for MEMS Product
Mirrorcle Technologies, Inc. provides a variety of optical microelectromechanical system (MEMS) products and services, including single and dual axis mircomirror scanners and low-inertia reflectors that use data acquisition. The system is capable of displaying a variety of vector graphics as well as multi-frame animations at arbitrary refresh rates.

Power Station Transformer Monitoring with the DT9832
Transformers are an electrical device that transfers energy from one circuit to another by magnetic coupling with no moving parts. These high voltages comes the need to monitor the transformers with a data acquisition system and insure they are running at an optimum and that no catastrophic events (explosions) can happen.

Rotating Speed Measurements with the DT9836
Quadrature encoders are used in a wide range of applications relating to rotating objects. They are used for positioning purposes and also to measure the rotating speed of an object. For many data acquisition applications, not only the position and the rotating speed of a device is of interest but physical and electrical data has to be acquired along with the rotating object.

Shock Testing Using the DT9836 Module and Measure Foundry
Quanta Laboratories needed a data acquisition system with the ability to measure 24 inputs, each with up to 2000 g of resistance, simultaneously. In addition, they wanted to be able to trigger the start of acquisition using a single-axis accelerometer.

Synchronized, Triggered Automotive Data Gathering Using Measure Foundry and DT9836 Hardware
Imagine that you need to capture multiple channels of high-speed, high resolution, simultaneous data in real time with absolutely no missed samples. A large automotive component manufacturer that supplies equipment to major car manufacturers faced this challenge and needed an appropriate data acquisition system.

Streaming Continuous Data at 10 GB/Minute Using the DT9862 USB Module and LabVIEW
This app note describes how a customer who needed to acquire precise measurement data from two analog input channels simultaneously at 10 MHz and continuously stream this data to system memory for several minutes was able to use the DT9862 with LV-Link 3.0.

The Evolution of Virtual Instrumentation
A virtual instrumentation system is computer software that a user would employ to develop a computerized test and measurement system, for controlling from a computer desktop an external measurement hardware device, and for displaying test or measurement data collected by the external device on instrument-like panels on a computer screen.

Using MATLAB for Data Acquisition

Using Quadrature Encoders/Decoders For X/Y Positioning and Rotation
A quadrature encoder is device used to sense position and rotation by converting displacement into digital pulses. A quadrature decoder takes the output signals from the quadrature encoder as inputs and converts these signals into a numerical value that can be used to determine position, distance, velocity, and other parameters. This paper describes how to use the quadrature decoders on the DT9836 Series module with a quadrature encoder to determine x/y position and rotation information.

When An Alternate Energy Source Fails, What Do You Do?
Many completed projects for roads, bridges, highways, trains, power facilities such as solar, wind and other machinery are in place and operating. But when neighbors complain about high noise levels or the facility fails, what do you do?

Isolation

Isolated Inputs Offer New Application Advantages
Protection from noise and ground loops with new ISO-Channel architecture that provides channel-to-channel isolation using an A/D per channel with a DC-DC converter for each A/D.

Why ISO-Channel Technology is Your Best Return on Investment
When connecting signal sources it is important to eliminate the sources of error that can contribute to inaccuracies in your measurements. In most measurement instruments, this burden is on the customer. Instruments that use ISO-Channel technology solve this problem for you – saving you tremendous setup and debug time and reducing costly grounding problems when connecting signals.

Sound and Vibration Analysis

Whole Body Vibration Exposure to Train Passenger
A DT9837 with MATLAB was used to evaluate Whole Body Vibration exposure to frequent train passengers.

Comparative Assessment of Vibration Exposure at Different Car Speeds
The purpose of this study is to evaluate and validate the vibration exposure experienced by a car driver.

Measuring Vibration Using the DT9837 and MATLAB
Vibration measurements are critical in predictive maintenance and diagnostic fault testing applications for quality assurance. Typical vibration applications use IEPE (ICPTM) accelerometers to measure vibration and when coupled with MATLAB®, a well known interactive software environment for data acquisition and analysis, report generation, and test system development, provide a complete set of tools for acquiring and analyzing vibration measurements.

Designing a Vibration Measurement Application With LXI
New cell phones, PDAs, Netbooks, and fancy consumer devices are being introduced at breakneck pace. These developments must get to market quickly, and assuring their integrity requires that severe shock and vibration testing is done faster and better than ever before. The emergence of the LXI standard holds the promise of plugging together off-the-shelf measurement boxes that can quickly accomplish these vibration tests.

Using MATLAB for Vibration Measurements
Vibration measurements are critical in predictive maintenance and diagnostic fault testing applications for quality assurance. Typical vibration applications use IEPE (ICPTM) accelerometers to measure vibration and when coupled with MATLAB®, a well known interactive software environment for data acquisition and analysis, report generation, and test system development, provide a complete set of tools for acquiring and analyzing vibration measurements.

Temperature Measurement

Advances in Ultra-Accurate Temperature Measurement Design
Temperature is the world's most widely measured property. Most temperature measurement instruments deployed today rely on technology architectures developed when silicon-based devices were far more costly and DOS ran computers. New approaches to analog design have changed this paradigm. This paper describes how the latest techniques in analog technology can be applied to the development of ultra-accurate temperature measurement instruments.

AMS2750D Temperature Uniformity Surveys using TEMPpoint
Industrial process furnaces and ovens require uniform temperature and heating; This is critical to repeatable product performance from batch to batch. These furnaces require periodic inspection for temperature uniformity. Using TEMPpoint to monitor temperatures over time according to AMS2750D specifications fits this application perfectly.

Avoid Pitfalls in Precision Temperature Measurement
Exact temperature measurement in many scientific, industrial, and commercial applications has driven the hunt for ultra accurate temperature measurement equipment capable of reading changes of a fraction of a degree Celsius. In addition, temperature measurement and control solutions must be easy to implement and use by both novice users and experienced engineers. New equipment and standards such as LXI have made a challenging task possible.

Channel to Channel Accuracy
When you need to measure temperature from multiple channels with precision, you want high accuracy and minimal variation from one channel to another.

LXI System Setup is Quick and Easy: A Complete Example
LXI-compliant instruments demonstrate predictable operation and behavior that make them easy to set up, configure, and debug. Find out just how easy it is.

Temperature Uniformity Monitoring: Biotech
A leading biotechnology company needed to evaluate freeze-dryers from a number of suppliers to select the best performing product for use in their processes to develop/monitor biological therapies. Temperature uniformity was considered the key indicator of product performance.

Temperature Uniformity Monitoring: Composite Curing Oven
A leading supplier of advanced composite materials was developing a new composite material and needed to get two, large curing ovens up and running to get their product to market quickly. Temperature uniformity was considered the key measurement requirement when evaluating the curing process.

Testing Lithium-Ion Batteries using TEMPpoint
Advances in battery technology have revolutionized the consumer market – powering products such as cell phones and laptops to hybrid cars. Lithium-ion batteries are the predominant power source for these devices because of their ability to store a great deal of energy in a compact, light package. Find out how a major manufacturer overcame testing difficulties using TEMPpoint for temperature data acquisition.

Transportation

Engine Monitoring and Testing with the DT9836
Engines are the driving force behind many forms of transportation and/or agricultural machinery. They are designed to run at high speeds and at high temperatures. They are stringently tested to perform under the harshest of conditions in order to satisfy very high quality standards. This testing process using data acquisition needs to be accurate, precise, repeatable, and most of all correct.

Ground Penetrating Radar for Road Maintenance Using the DT9832
A road maintenance/ground penetration analysis company provides analysis and data recording of newly laid asphalt roads. The company presently does this with the use of about a half a dozen specially equipped RV's. They were looking to use a lower cost, high speed, portable data acquisition device which had the ability to keep up with the vehicle when driving at speeds up to 60mph while performing the radar pass over the newly laid asphalt.

Lightning Mapping System Bolsters Air Travel Safety
Researchers at the Langmuir Laboratory for Atmospheric Research at the New Mexico Institute of Mining and Technology have been getting a real charge out of their work. They have developed a system for mapping lightning that measures radiation to produce a three-dimensional map of lightning activity and it has been enhanced with Data Translation's DT301 PCI data acquisition board.

Synchronized, Triggered Automotive Data Gathering Using Measure Foundry and DT9836 Hardware
Imagine that you need to capture multiple channels of high-speed, high resolution, simultaneous data in real time with absolutely no missed samples. A large automotive component manufacturer that supplies equipment to major car manufacturers faced this challenge and needed an appropriate data acquisition system.

Understanding Specifications and Accuracy

ENOB (Effective Number Of Bits) – The Accurate Way to Choose a Data Acquisition Board
In choosing a data acquisition board, there is probably no more important specification than its overall accuracy – that is, how closely the output data reflects the input signal. Your vibration analysis, sensor readings, audio recording, and temperature measurements can be no more accurate then your data acquisition board.

Measuring Dynamic Performance
This white paper describes the importance of AC specifications when measuring dynamic performance, including the Nyquist theorem. Also, in applications where you want to measure rapidly changing and/or high frequency signals, ENOB (Effective Number of Bits) and SFDR (Spurious Free Dynamic Range) specifications can help you characterize dynamic performance.

The Battle for Data Fidelity: Understanding the SFDR Specification
As A/D converters (ADC) and data acquisition boards increase their bandwidth, more and more are including the spurious free dynamic range (SFDR) specification as an indicator of their fidelity. The key to properly interpreting this specification lies in understanding the sources of spurious signals and how SFDR is measured.

White Papers

Data Acquisition Fundamentals:
Improving Measurement Quality with Signal Conditioning
This white paper explains the best practices and proper application of the seven major signal conditioning types. Understanding the unique characteristics of each technique will help improve the measurement accuracy of your data acquisition system.

Making Accurate Temperature Measurements with Thermocouples, Thermistors and RTD Sensors
This in-depth white paper explores the theory, operation, and pitfalls of using thermocouple, thermistor, and RTD sensors. Find out how to improve the accuracy and reliability of data from these sensors.

Digital and Pulse-Train Conditioning
Learn about digital I/O signals and interfacing, isolation, pulse-train signal conditioning, frequency-to-voltage conversion, timing applications, and more.

Noise Reduction and Isolation
Learn about controlling noise, ground practices, shielding, isolation, and crosstalk in data acquisition systems.

Displacement and Position Sensing
Learn about displacement and position sensing. Topics include linear displacement, linear variable differential transformers, rotational position, and more.

Electrical Measurements
Learn the priniciples behind making valid voltage measurements including high and low AC and DC levels. Topics also include current and resistance measurements, RMS, hall effect sensors, voltage dividers, and more.

Multiplexing and Sampling Theory
Learn about sampled data acquisition systems, fundamental concepts of sampling rates, sample and hold circuits, aliasing and fourier transforms, filtering, settling time, and more.

Analog to Digital Conversion
Learn how analog to digital converters operate including successive approximation, integrating, and Sigma-Delta ADCs. Topics also include ENOB, measurement accuracy, resolution, and more.

Making Basic Strain Measurements using 24-Bit Hardware
Learn about the basic principle of operation of strain gages, the various ways in which they may be connected, and the requirements of their signal conditioners to reduce susceptibility to noise that can contaminate their low-level output signals.


MCC White Papers of interest:
MCC DAQ HATs – Supporting Raspberry Pi® in OEM and Test and Measurement Applications
Raspberry Pi has quickly moved from being a cheap computer designed for children into the hobbyist/maker market and increasingly into industrial/commercial markets. MCC’s family of DAQ HATs are specifically for the Test and Measurement and OEM/ODM markets.

5 Steps to Creating and Deploying Android™ Data Acquisition Apps
With the Universal Library (UL) for Android API, you can easily create custom data acquisition apps for Android devices. UL for Android communicates with supported Measurement Computing DAQ devices over the Android 3.1 platform (API level 12) and later.

Tablets in Data Acquisition
In the drive to smaller and smaller data acquisition systems, tablet computers bring a great appeal. Desktop personal computers gave engineers the power to create custom test and measurement applications. Laptop computers gave engineers the ability to create smaller and more portable DAQ systems. Are tablet computers the natural evolution of this trend?

Guide to DAQ Signal Connections
This new guide provides an overview of wiring configurations, techniques, and best practices for data acquisition signal connections. Readers will learn about proper grounding, common mode voltages, single ended vs. differential inputs and more.


DASYLab Techniques:
- Saving DASYLab Data to an ASCII Readable File
- Using Cursors in the Display Modules
- Create a Worksheet: Save a New File at Midnight Every Day
- Create a Worksheet: Collect, Display, and Save Temperature Data