Vibration testing can be a complicated process. We have created this questionnaire to help make communication between the vibration test lab and customer more efficient. The questionnaire allows us to capture all the pertinent facts about your test requirements. Providing the information below will help us provide an accurate quotation and to perform a successful vibration test. We can help you with answering the questions if needed. Many engineers, not familiar with vibration and shock testing, a subject not taught by universities, may wish to further their education. May we respectfully suggest that you visit http://equipment-reliability.com/training-calendar/vibration-and-shock-testing/ for vibration and shock training courses.
1: What are the vibration test specifications?
A: Please list any required test specifications such as MIL-STD-810 or RTCA DO-160 or IEC?
B: What is the type of vibration (random, sinusoidal, etc.)?
C: What is the acceleration level in G’s or m/s2?
D: What is the frequency range?
E: How many axes to be tested?
F: What is the duration per axis?
G: Please provide other known details such as sinusoidal sweep rate, number of sweeps, random vibration PSD profile
There are many different vibration test specifications. Many times the questions above are clearly answered in a test specification such as MIL-STD-810G. However sometimes they are not and the customer will need to provide further details. A good vibration test lab can help you answer the questions above.
2: Is combined temperature and vibration required? If yes, please answer the sub questions. If no skip to the next question.
A: What are the maximum or minimum temperatures?
B: Are the temperatures constant or cyclic?
C: If cyclic, please define the temperature cycle parameters such as number of cycles, temperature transition rates and the dwell times at each maximum and minimum temperature.
3: Please provide information on the products or Devices Under Test (DUT’s).
A: What are the dimensions of the DUT and what is the mounting foot print?
(A drawing or sketch or picture with some overall dimensions is usually helpful)
B: How much does the DUT weigh?
C: How many DUT’s will need to be vibration tested?
This information is required to assess vibration test fixtures and also to determine if the DUT will fit on the vibration shaker table. Remember vibration shakers are rated for maximum force. The maximum force is determined from the formula
Force = Mass (or Weight) x Acceleration
The units for Mass are usually pounds or kilograms and acceleration is usually given in G’s or m/s2.
It is important to note that the Mass is not only from the DUT’s but is:
MASS or Weight = weight of shaker armature + shaker table (slip table or head expander or cube or angle fixtures) + DUT fixture + DUT’s + weight of any other adapter fixtures or significant added moving weight.
The customer only needs to provide the weights of components they are supplying such as the products to be tested, the fixture weight if they are supplying the fixture, and any other significant moving weights attached to the shaker such as heavy cables.
4: Who will supply the DUT fixture? (Customer or Test Lab)
The DUT will have to be attached to the vibration table by some means. Typically clamps or a flat aluminum adapter plate are used. The adapter plate is bolted to the vibration table and the DUT is bolted to the adapter plate. Vibration test fixtures can be simple or elaborate depending upon the DUT and test requirements. A good fixture design is important for a successful vibration test. It is important to have good communication with the vibration test lab about vibration test fixtures so that no surprises occur before the start of the vibration test.
5: Does the DUT need to be powered and monitored during the test? If yes, please answer the sub questions. If no skip to the next question.
A: What are the power requirements
i: What is the voltage
ii: Is it AC or DC?
iii: What is the power or current required?
iv: Is it single or 3 phase?
v: If AC current, what is the frequency (Hz) required for the electrical power source?
vi: Any special electrical loads required?
B: Who will provide the power source if a special source is required? (customer or test lab)
C: What are the monitoring requirements to verify that the DUT is operating properly during the test? (This can be as simple as visual observations of LEDs or continuity measurements or comprehensive electrical measurements)
D: Who will provide the necessary equipment required to monitor the DUT? (customer or test lab)
6: Do you need response accelerometers to measure any DUT resonances? If yes, please answer the sub questions. If no skip to the next question.
A: How many response locations do you need?
B: Do you need single or three axis accelerometers?