Set up and perform a sine vibration test with ease
Automatically detect resonances using a swept and/or fixed-frequency sine wave test with control of acceleration, velocity, and displacement. Then, use a sine resonance tracked dwell (SRTD) test to determine the number of cycles required to generate a failure at a specific resonant frequency. Sine features include easy test entry, configurable tracking filters on input channels, and a large numeric readout.
Enter frequency/amplitude breakpoints in an easy-to-read, tabular format. The operator can select to control constant or ramped acceleration, velocity, or displacement. Automatically calculate and enter the frequency of intersection between any combination of constant acceleration, velocity, or displacement lines. Over 1,024 separate frequency/amplitude breakpoints can be entered, allowing entry of virtually any test specification.
Configure from 1 to 256 input channels with either multi-channel averaging or multi-channel extremal control. A standard frequency range is DC-4,990Hz which can be extended up to 50,000Hz with the VR9103 High-Frequency option. These inputs allow for more than one input channel (multi-channel extremal) for control in a control strategy where the highest, lowest, or average of accelerometer readings will be used for control of the test.
Linear sweep type (Hz/minute or minutes/sweep) or logarithmic (octave/minute, decade/minute, minutes/sweep) sweeps can be specified and changed while running the test. The test duration can be entered in terms of length of time, number of sine wave cycles, or number of sweeps. Sequences of fixed-frequency tones of a specified acceleration, velocity, or displacement can be run. Looping functions allow easy entry of repeating tone sequences. Input channels have individually selectable tracking filters (user-configurable) to remove harmonics and out-of-band noise from the measurements.
Sine Big Display
A configurable large numeric readout displays the current test frequency and channel amplitudes. Use the manual control to manually control the sweep direction, sweep rate, and scale the amplitude with your mouse cursor.
Configurable safety limits
The controller can be configured to abort if the controlled acceleration goes above or below the desired level by an operator-configured number of dB. Abort limits can also be enabled for individual monitoring channels. Drive limits can be configured to protect from overdriving your shaker in case of failed accelerometers.
Sine Fundamentals Webinar
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What is sine vibration testing?
A sine vibration test outputs a single frequency sine tone at a defined amplitude and time. It is most often used to determine resonances and to expose the test item to a resonant frequency until failure.
There are several ways to conduct a sine test. A sine sweep exposes the test item to a sine tone with a frequency that varies across a defined range. After the sine sweep, the test engineer can determine the resonant frequencies of the test item. Then, the engineer can expose the test item to the resonant frequencies until failure or until enough time is spent at each resonant frequency to ensure a failure will not occur. A sine test sends all the shaker’s power to the resonant frequency where the failure will occur.
A basic test that is simple to set up and perform
One of the best methods for identifying resonances
An effective way to bring a test item to failure if the failure arises from the excitation of a known resonance
Should I use a sine or random vibration test?
A sine test outputs a single frequency sine tone at a defined amplitude and time. A random vibration test outputs random vibration that, throughout the test, include the entire frequency range of the test. Random testing is more realistic than sine testing because real-world vibration is inherently random. However, sine is a more suitable test method for:
Identifying resonances in a test item.
Identifying issues with the shaker system (cracked armature, loose bolts, etc.). Variations in the response, especially if there are resonances that shift significantly, indicate there is an issue in the shaker system.
Validating Fixtures. If the fixture has resonances in the test frequency range, the results of the test will be questionable.
Qualifying a product if product failure arises from the excitation of a known resonance.
What is a resonance in vibration?
Resonance occurs when the frequency of an external force is the same or nearly the same as the natural frequency of a structure. The frequency response of the structure is amplified when its natural vibration is excited, which can result in structural fatigue or damage.
When should I run a sine sweep test?
Engineers use a sine sweep test to find the resonant frequencies of a test item. The identification of these resonant frequencies is essential for product development and qualification. A resonance test such as the sine sweep should be performed if a test engineer needs to identify and observe a product’s response to a resonant frequency.
What is sine resonance track & dwell (SRTD)?
A test engineer may run a sine resonance track & dwell (SRTD) after they have determined the resonances of a test item with a sine sweep. SRTD is meant to bring a product to failure by exciting a known resonance.
During a sine dwell test, the vibration controller runs a single sine tone at the product’s resonant frequencies rather than sweeping through the frequency range. A product experiences the most fatigue when exposed to its natural resonance. The test is run until failure occurs, or sufficient time has passed without failure.
Sine Resonance Phase Track & Dwell Software
Transmissibility peaks can be automatically detected from a sine sweep, and then dwell tests run at the detected resonance frequencies for a specified time duration or number of sine wave cycles. In a sine dwell test, the controller can automatically track the resonance frequency to keep the output on resonance even when fatigue damage causes the resonance frequency to shift. Track High Q or sharp resonances with advanced phase tracking controls that allow you to dial in on resonance and maintain peak amplitude by way of Phase vs. Transmissibility.