UltimaSerial Third party activex control that provides interface and charting utility to WinDaq devices. WinDaq add-on that allows acquired data to be ported to a Microsoft Excel spreadsheet. WinDaq Add Ons. Free playback and analysis software required to review files recorded by WinDaq software. Injection Molding Machines.
Who Stopped the Music? WinDaq Applications in Medical Research. Waveform Analysis Using the Fourier Transform. Reducing Sample Rates Even Further. Engineering Units Scaling and "Set Offset". Breaking Down Lengthy Recordings. Slow Sample Rates Explained. New bit Convert Beta Available. In Stock. Fast Start Guide. Includes frequency analysis, digital filtering, X-Y plotting, and statistical analysis WinDaq software is included with most DI- Series data acquisition hardware products, and consists of two applications: Recording and Playback software.
Compatible Products. Learn More. Disk and Display Acquisition Software Maximum continuous throughput to disk: Hardware dependent Maximum continuous real-time display throughput: Hardware dependent Waveform Display Modes: Continuous smooth-scrolling; freeze; triggered and non-triggered sweep.
Dot-joined at all sample rates. Waveform Compression: Allows display rate to vary independently of sample rate. Compression factors of 1 no com-pression to 9, Number of displayed channels: 1 to 32 Number of acquired channels: 1 to Display formats: Overlapping 2 channel max and non-overlapping. Software selection of: Amplifier gain and input configuration for hardware products supporting programmable gain.
Grid Scaling: Allows each displayed channel to be scaled between user-defined limits. Hard Copy Acquisition Software Hard Copy: Supports print screen hard copy in the background regardless of disk streaming activity. Because physical phenomena exist in the analog domain, i.
This process is done using a variety of sensors and signal conditioners. The outputs are sampled by analog-to-digital converters ADCs and then written in a time-based stream to a digital memory media, as mentioned above. We usually call such systems the measurement systems. A complete scheme of an analog data acquisition system. The measurement of a physical phenomenon, such as the temperature, the level of a sound source, or the vibration occurring from constant motion, begins with a sensor.
A sensor is also called a transducer. A sensor converts a physical phenomenon into a measurable electrical signal. Sensors are used in our everyday lives. For example, the common mercury thermometer is a very old type of sensor used for measuring temperature. Using colored mercury in a closed tube, it relies on the fact that this chemical has a consistent and linear reaction to changes in temperature.
By marking the tube with temperature values, we can look at the thermometer and see what the temperature is with limited precision. The classical thermometer is used to measure temperature for centuries. Of course, there is no analog output other than the visual one.
This kind of primitive thermometer, while useful in the oven, or outside the kitchen window, is not particularly useful for data acquisition applications.
So other types of sensors have been invented to measure temperatures, such as thermocouples, thermistors, RTDs Resistance Temperature Detectors , and even infra-red temperature detectors.
Millions of these sensors are at work every day in all manner of applications, from the engine temperature shown on our automobile dashboard, to the temperatures measured in pharmaceutical manufacturing. Virtually every industry utilizes temperature measurement in some way. Temperature sensors: from left to right: thermocouple, thermistors, RTD sensor. Of course, there are many other types of sensors that have been invented to measure another physical phenomenon:.
Depending on the type of sensor, its electrical output can be a voltage, current, resistance, or another electrical attribute that varies over time. The output of these analog sensors is typically connected to the input of a signal conditioner, which we will discuss in the next section. What is a sensor or transducer guide? How to measure strain and pressure using strain gauge sensors? How to measure weight with load cell sensors? Signal conditioners are in the business of taking the output from analog sensors and preparing them to be sampled digitally.
If we continue the example of the thermocouple. The signal conditioning circuitry needs to linearize the output from the sensor as well as provide isolation , and amplification to bring the very small voltage up to a nominal level for digitizing. From analog signal source to digitalized data ready for processing by computer and software. Each signal conditioner is designed by the manufacturer to perform the elemental normalizing of the sensor output to ensure its linearity and fidelity to the source phenomena, and prepare it for digitizing.
And since every sensor type is different, the signal conditioners must conform perfectly to them. What is signal conditioning or signal conditioner guide? Sometimes also referred to as galvanic isolation , electrical isolation is the separation of a circuit from other sources of electrical potentials. This is especially important with measuring systems because most signals exist at relatively low levels, and external electrical potentials can influence the signal quality greatly, resulting in wrong readings.
Interfering potentials can be both AC and DC in nature. For example, when a sensor is placed directly on an article under test, e. Electrical interference or noise can also take the form of AC signals created by other electrical components in the signal path or in the environment around the test. For example, fluorescent lights in the room can radiate Hz which can be picked up by very sensitive sensors.
This is why the best data acquisition systems have isolated inputs - to preserve the integrity of the signal chain and ensure that what the sensor outputs is truly what has been read. There are several kinds of isolation techniques employed today.
Video explaining high galvanic i solation on Dewesoft data acquisition systems. Virtually every signal that we want to measure can be affected by electrical interference or noise. This has a variety of causes, including ambient electromagnetic fields which can be induced into high gain signal lines, or simple voltage potentials that exist between the sensor or measuring system and the object under test. Therefore, the best signal conditioning systems provide selectable filtering that the engineer can use in order to remove these interferences and make better measurements.
In this scheme, a noise analog signal is passed through a low pass filter to filter unwanted frequencies. Filters are normally expressed in terms of the band that they operate upon.
In this picture, the green input signal top is a triangular signal with a frequency of 1. The signal is sampled with a frequency of 1 kHz. The positions at which the signal is sampled are depicted with the blue dots. The red dotted signal bottom is the result of the reconstruction. The period time of this triangular signal appears to be 4 ms, which corresponds to an apparent frequency alias of Hz 1.
In practice, to avoid aliasing, always start measuring at the highest sampling frequency and lower the sampling frequency if required. Use function keys F3 lower and F4 higher to change the sampling frequency in a quick and easy way.
The next illustration gives an example of what aliasing can look like. In this picture, a sine wave signal with a frequency of kHz is sampled at a frequency of 50 kHz. The minimum sampling frequency for correct reconstruction is kHz. For proper analysis, the sampling frequency should have been approximately 5 MHz. With a given sampling frequency, the number of samples that is taken determines the duration of the measurement. This number of samples is called record length. Increasing the record length, will increase the total measuring time.
The result is that more of the measured signal is visible. In the images below, three measurements are displayed, one with a record length of 12 samples, one with 24 samples and one with 36 samples.
The total duration of a measurement can easily be calculated, using the sampling frequency and the record length:. Changing the record length of an instrument in the Multi Channel oscilloscope software can be done in various different ways:. The combination of sampling frequency and record length forms the time base of an oscilloscope. To setup the time base properly, the total measurement duration and the required time resolution have to be taken in account.
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