Request a Return Merchandise Authorization number for repairs and recalibrations.
Start RMANIST traceable calibration. IST recommends annual re-calibration for all recorders. Certified to MIL-STD-45662A and ISO Z 540 compliant.
Learn MoreRepairs and recalibration, with an Expedite Service to get your system back within days. If we cannot return your unit as promised, the expedite fee is waived.
Learn MoreLimited product warranty, software warranty, and extended warranty options for all systems.
Learn MoreNotes and references on shock & vibration, including ASTM and ISTA standards.
View ReferencesIST recommends annual re-calibration for all recorders. We provide a complete recalibration service to help keep your system providing accurate results. IST has been certified to MIL-STD-45662A and is ISO Z 540 compliant. All calibrations are traceable to the National Institute of Standards and Technology (NIST).
We request customers contact IST Technical support or get an RMA number before returning equipment.
To ensure the best possible turnaround time on non-warranty repairs and recalibrations, IST offers an Expedite Service. IST will get your system back to you within days. Availability of this service is subject to our production schedule, and the needs of other customers as well. If we cannot return your unit as promised, the expedite fee is waived.
To expedite your order call or email ahead to arrange it. Note that your order will be moved to “next in line” status, but your order can be superseded by any order classified as a US Defense Priority, per applicable law.
IST warrants its instruments are free of manufacturing defects for one year from the delivery date. If a defect is discovered within this period, IST will repair or replace the product within a reasonable time. We reserve the right to decide whether the product will be replaced or repaired. This warranty is limited to defects that are found to be due to IST’s manufacturing or testing procedures. The warranty does not apply to accessories such as batteries, accelerometers or cables that are manufactured by others. By using instruments and accessories manufactured by IST or its suppliers, the customer agrees that IST is not liable for any losses suffered as a result of this use and agrees to the conditions of this warranty.
IST guarantees its software programs only to the extent of replacement for one year from the delivery date. IST will replace, at no charge, any software programs supplied by IST that are found to be defective. By using software supplied by IST, the customer agrees that IST is not liable for any losses suffered as a result of this use and agrees to the conditions of this warranty.
At the time of purchase, you may choose to extend the warranty coverage beyond the standard one year. IST offers extended warranties for all systems for two, three or five years from the date of manufacture. Extended Warranties cover the cost of the recommended yearly recalibration, as well as all repairs that may be needed.
It is very likely that you will be measuring random vibration events with IST products. Random vibration can be understood as a non-periodic or statistically varying oscillation or motion about a reference point. Common sources of random vibration include shaking airplane wings during flight, a car driving down a rough road, an earthquake, or an elevator shuddering on the way up. Understanding and measuring random vibration is important, since it can cause stress, fatigue, failure, or damage to the object experiencing the vibration.
Vibration measurements are often taken as accelerations measured in g’s. One g is equal to 32 ft/sec² or 9.8 meters/sec², the acceleration due to gravity near the surface of the earth. Acceleration is an effective way to measure vibration events because the velocities and displacements during these events are often very small. What are “normal” accelerations? Many people are unfamiliar with the accelerations everyday objects experience. The figure below will help you gain an understanding of the range of accelerations you may encounter while using IST instruments.
Some examples of acceleration (axis not to scale). Values are approximate and for reference only. Some of these values may be surprising, but, as explained in the next section, the mass of an object under acceleration plays a big role in how it responds. In general, objects with smaller masses can withstand more acceleration than those with larger masses.
Several IST recorder products record peak acceleration. Why is this important? The maximum acceleration is important because it helps describe the forces the object in question is dealing with. Newton’s Second Law states that the force an object experiences is equal to the mass of that object multiplied by the object’s acceleration. The equation is:
F = MA
Where F is the force, M is the mass of the object, and A is the acceleration of that object. Measuring the maximum acceleration events an object experiences provides insight into the maximum forces acting on the object, and therefore potential damage or failure.
The “rms” or “root mean square” is a statistical calculation which provides a means of quantifying vibration fluctuation or average amplitude. The root mean square is defined as the square root of the mean of the squared values of the data set. The rms is frequently used to quantify a random vibration event for a specified time period. This is useful as raw acceleration readings can be difficult to interpret by themselves. In the field of vibration g-rms is simply the rms of a set of acceleration data measured in g’s. IST software easily computes g-rms for measured vibration events from recorders.
Another useful statistic when dealing with vibration data is the crest factor (CF). The crest factor is a dimensionless measurement of a waveform. It is calculated as the peak amplitude of a waveform or data set divided by the rms. The crest factor quantifies how extreme the peak value is relative to the rms level in, for example, a vibration data set. The minimum value the crest factor can theoretically attain is 1, which represents the CF for an ideal square wave. A sine wave has a CF of 1.414, and the theoretical maximum for the crest factor is infinity.
For further information about shock and vibration, measurement methods, and application, use these helpful references:
From satellite transportation to airborne vibration and crash testing, IST delivers high-performance recording solutions for demanding Aerospace & Defense applications. The EDR-5 and EDR-5D provide reliable measurement and recording for critical shock and vibration environments.