A customer approached DES looking to find an accelerated test solution for an AC powered cooling fan used in one of their products.  The product had been established in the marketplace and the company was now looking for ways to reduce cost by looking at different cooling fan suppliers.  Most fans, however, have a mean life rated for over 20,000 hours, so a typical accelerated life test would require a significant amount of time and money. 

DES Solution

Performing a quantitative accelerated life test on cooling fans presents challenges because they have such a long lifespan.  Reasonably speaking, the shortest quantitative solution for determining the lifespan of a fan could take as long as a couple months.  DES proposed a qualitative solution, a Rapid HALT.  A Rapid HALT (Highly Accelerated Life Test) is designed to apply a variety of stresses, concurrently, to a product in order to significantly time compress a product’s lifespan.  A typical Rapid HALT lasts only one day which is extremely convenient for companies that need results quickly.

Results

A sample size of 3 cooling fans were tested for 4 different fan suppliers.  We will refer to these suppliers as Supplier A, B, C and D.  All 12 fans were placed in the chamber together and a Rapid HALT was conducted.  None of the four suppliers survived testing without some issues but the results were still differentiating.  Supplier A had no electrical issues in any of its samples but the fan blades on all 3 samples vibrated off the armature.  Fans of Supplier B, all experienced sputtering of the fan blade and eventually saw two of its fans current levels drop to 0.  By the time testing was completed, none of the fans were functioning.  Supplier C fared slightly better than A and B.  One of Supplier C’s fans lost current at the most extreme step and never recovered.  The other two however, experienced fan blade sputtering but were functioning normally upon final inspection.  Supplier D performed the best out of the four suppliers and thus would be considered the most durable of the suppliers tested.  Only one of the fans experienced any issues, in which it lost current at the most extreme step.  Upon final inspection all of the fans were functioning normally.

There are other factors to consider such as price and accessibility but these results were able to successfully assist our customer in differentiating between the reliability of the four fan suppliers.  While a HALT is qualitative and will not produce an actual estimated fan lifetime, it is a great comparison tool to evaluate the reliability of different suppliers faster and less expensive than traditional testing techniques.

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If the product fails to operate, the temperature or vibration will be changed toward ambient room conditions followed by a short dwell period to see if the product recovers. If the product is non-operational after dwelling at ambient conditions, trouble shooting will take place to find the failed component. The failed component will then be removed, repaired or replaced with a new component (as is practical) in an effort to expand the test stresses.

Relevant Failures

All HALT failures are relevant unless it is determined that the failure was caused by a condition external to the product which is not a test requirement. Relevant failures may include, but are not limited to the following:

• Design and Workmanship Failures
• Failures caused by Poor Manufacturing
• Component Part Failures
• Multiple Failures
• Intermittent Failures
• Built-in-Test Failures

All relevant failures represent an opportunity for improvement and should be thoroughly investigated to determine their root cause. All relevant failures should be evaluated as to whether or not they can be corrected with a reasonable amount of effort and cost. However, all failures that prevent a product from functioning in its normal environment should be fixed! Figures 1 through 3 show examples of relevant HALT failures.

In Figure 1, the mounting tabs used to hold a power supply in place failed during vibration. Larger tabs with better stress relief grooves should be used in this case to better withstand the vibrations. The capacitor leads in Figure 2 failed due to repeated fatigue stresses from vibration. Improved mounting such as placing an adhesive under the capacitor could be used to prevent this type of failure which is common for large components connected by thin metal leads.

In the case of temperature related failures such as seen in Figure 3, the temperature at which failure occurred should be well outside of the expected operating range of the equipment.

Even in this case, an evaluation should be performed to determine if a component with an improved temperature rating can be economically substituted because the failing component may be a weak point in the product design.

Non-Relevant Failures

Failures listed below may be considered as non-relevant:

• Failures directly attributable to erroneous product manufacturing or operation.
• Failures resulting from improper test setup or procedure.
• Dependent failures, unless caused by degradation of items of known limited life.
• Failures occurring during test “down-time” such as during troubleshooting on the bench unrelated to the HALT Procedure.

Care should be taken when determining if a failure is non-relevant as this may result in missing an opportunity for product improvement.

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Specialized test chambers are needed to perform a HALT. Typical HALT chambers are shown in Figure 1. The specification for HALT chambers is typically the following:

Liquid nitrogen (LN2) is used to cool the air temperature in HALT chambers. This allows for very rapid temperature changes of 60°C per minute and a cold temperature extreme of -100°C.

HALT chamber heating is provided by high power resistive heating elements that can produce changes of 60°C per minute and a hot temperature limit of +200°C.

HALT chambers produce random vibration in 6 DOF simultaneously using pneumatic air hammers attached to the bottom of the chamber table. This means random vibration energy is applied simultaneous along three orthogonal translations and three rotations which is very unique to HALT chambers. Sometimes the vibration produced in HALT is called repetitive shock because pneumatic air hammers are used to produce vibration.

Random vibration accelerations up to 60 Grms and frequency content to 10,000 Hz are common. It is important to understand how the how HALT chambers compute Grms. DES’s HALT chambers calculate Grms using a 5 kHz bandwidth. Some chamber manufactures use a 10 kHz bandwidth which approximately doubles the computed Grms, but in reality the resultant vibrations are about the same! More information about random vibration can be found in our blog article Sinusoidal and Random Vibration Testing Primer

It is important that HALT chambers can be run in automatic or manual modes of operation. Temperature and vibration profiles are programmed to run automatically during parts of the HALT procedure. This allows the temperature rate of change to be accurately controlled during temperature transitions. The chamber can also be run in manual mode with the operator controlling the temperature and vibration set points. This is useful for other parts of the HALT procedure such as when operational or destruct limits are being determined.

Fixtures

DES’s has many stock channel fixtures that can be used for products with a flat top and bottom. Examples of DES’s stock channel fixtures are shown in Figure 2.

Custom-designed fixtures can be fabricated on a case by case basis. Figure 3 shows examples of custom-designed test fixtures. The fixtures must have a flat base with holes to enable them to be bolted to the chamber vibration table. Customers or DES can supply the fixtures used to attach the test units to the vibration table inside the chamber.

When performing HALT, it is desired to change the temperature of internal components as fast as possible. If products have existing vent holes or cooling fans, then air ducts can be placed to blow air through them as seen in Figure 2. Products with a sealed enclosure or case should be modified whenever possible to allow for internal airflow. This can be done by removing covers when practical or drilling holes in the enclosure. Air ducts can then be placed near these openings to direct air flow internally into the product.

Instrumentation and Monitoring

Monitoring can be accomplished with either digital recording instruments or by manually recording gauge readings or by visual observations. Monitoring sensors are usually thermocouples and vibration accelerometers. Reference thermocouples are placed at various locations on the product to measure the response temperatures on the product. Also, during the vibration step part of the HALT procedure, reference vibration accelerometers can be placed on the product to measure its vibration response. Therefore a digital temperature data recorder is needed and a vibration spectrum analyzer or Grms recorder is useful. HALT chambers will typically provide basic digital recording of the chamber temperature and table Grms. DES provides the equipment for recording all of the temperatures and vibrations. Many times the customer provides the equipment for monitoring the specific performance of their product. However, DES has the capability to provide all of the monitoring equipment and instrumentation if desired. DES has extensive experience in setting up custom monitoring to record many different parameters such as voltage, current, pressure, etc.

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Stage 1 is used to determine the HALT Operational Limits for temperature. The goal is not to cause destruction in Stage 1, but sometimes the operational and destruct limits occur simultaneously. The HALT Destruct Limits for temperature and vibration are typically found in Stages 3 to 5.

Temperature Step Stresses – Stage 1 (Figure 1)

Stage 1 is started with Cold Step Stresses. Testing is started at 10ºC and is decreased in 10 ºC increments until the lower operating limit is determined or the chamber minimum temperature of -100 ºC is reached.

The dwell time at each step is defined as the point when stabilization and saturation of the device and its components is achieved which is typically 15 to 20 minutes. Functional testing will occur during this stabilization period. The dwell time will be determined from temperature measurements obtained from thermocouples placed on the product. Thermocouple data from individual components that can be a source of heating or cooling are not used to define the dwell time.

The second part in Stage 1 is Hot Step Stresses. Testing is started at 40 ºC and increased in 10 ºC increments until either the upper operating limit is determined or the chamber maximum temperature of +200 ºC is reached. The dwell time will be established using the same procedure as for the Cold Step testing segment.

Note that the upper and lower temperatures may be reduced if material limitations, i.e., solder melting or plastic softening are exceeded. Also, it is good practice to perform a functional test of the product at room temperature or 25 ºC before starting a HALT to get baseline measurement on its performance.

Temperature Ramps – Stage 2 (Figure 2)

During this Stage, temperature cycles with rapid transition rates (ramps) will be applied to the product. The chamber air temperature will be changed at 60 ºC/minute. The hot and cold temperatures will typically range from 10 ºC above the lower operating limit to 10 ºC below the upper operating limit. These 10 ºC reductions are to allow for over shooting caused by changing the temperatures extremely fast. The dwell time, established in Stage 1, will normally be used at each hot and cold temperature. Five cycles are applied.

Vibration Step Stresses – Stage 3 (Figure 3)

A broadband vibration spectrum will be applied through the HALT chamber table. The HALT chamber table should apply random vibration energy to 10,000 Hz in 6 DOF (degrees of freedom). Vibration step stresses will start at 10 Grms and increase in 5 Grms steps until either the operating, the destruct limits, or the chamber maximum vibration level of 60 Grms is reached. At 40 Grms levels and above, the vibration step will be returned to 10 Grms for 1 minute to detect failures that could be hidden by extreme forces occurring at higher vibration levels. Dwell time at each step, will be approximately 15 minutes to accumulate fatigue damage. Grms is measured with a 5 KHz bandwidth. This test is performed at room temperature of approximately 20 to 25 ºC.

Combined Temperature & Vibration Stresses – Stage 4 (Figure 4)

Combined temperature and vibration stresses are applied in Stage 4. During this Stage, the chamber air is changed at 60 ºC/minute. The hot and cold temperatures are the same as those used in Stage 2. The dwell time at each hot and cold temperature will be the same as used in Stage 2. Vibration level is fixed during each temperature step and begins at 10 Grms and increases in 10 Grms steps until either the operating or destruct limits or the chamber maximum vibration level of 60 Grms is reached.

Temperature Destruct Limits – Stage 5 (Figure 5)

The cold temperature destruct limit is found by starting at the lower operating limit (found in Stage 1) and decreasing the temperature in 10 ºC increments until either the low temperature destruct limit or the chamber minimum temperature of -100 ºC is reached. The hot temperature destruct limit is found by starting at the upper operating limit (found in Stage 1) and increasing the temperature in 10ºC increments until either the hot temperature destruct limit or chamber maximum temperature of 200 ºC is reached. The dwell time established in Stage 1 is used typically, however dwell times may be reduced if the product stops operating or if failures occur. If the product fails to operate, the temperature will be reduced or increased towards 20 ºC to see if the product recovers. If the unit is non operational after stabilizing at 20 ºC, the product will be repaired (if practical) so that the test temperatures can be expanded. If it is not practical to repair the product, Stage 5 will be terminated.

Power On/Off Cycling

Powered on/off cycling is recommended at every temperature or vibration step to create additional electrical stresses. These power cycles will be conducted quickly but sufficient time will be allowed so as not to create artificial excessive overloads and failure modes. Powered on/off cycling may not be appropriate for every product as it may create artificial stresses and failure modes, or the product may take too long to power up.

Test Samples

The typical number of products tested simultaneously is 1 to 4 as practical based on the cost and size of the products. Additional spare parts or backup units (not under test) may be needed for spare parts to repair and continue with testing if a non-repairable failure occurs.

Test Reporting

High quality test reports written by DES will contain, at a minimum, plots similar to those shown in Figures 1 to 5. These plots will include measured chamber control temperature, vibrations and product response temperatures, vibrations along with an indication of where each failure or significant event occurred during the HALT. Additionally plots of test voltages, currents, pressures or other applicable parameters will be included as applicable. The report will also contain identification of samples, a list of test equipment and personnel, photographs of the test setup including response sensor locations, photographs of any physical failures and a summary of the test procedure and results.

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HALT can be effectively used multiple times over a product’s life time. During product development, it can find design weakness when changes are much less costly to make. By finding weaknesses and making changes early, HALT can lower product development costs and compress time to market. When HALT is used at the time a product is being introduced into the market, it can expose problems caused by new manufacturing processes. When used after a product has been introduced into the market, HALT can be used to audit product reliability caused by changes in components, manufacturing or suppliers etc. The bottom line is that HALT can reduce product development time and cost, reduce warranty costs, improve customer satisfaction, gain market share, and increase profits.

HALT is not a qualification test, thus there are no predetermined pass/fail criteria. The goal of HALT is to quickly precipitate failures and then to determine their root causes. Once the causes of failure are determined, the failed components are repaired and the stress limits of the testing program are expanded.

Important HALT Definitions

6 Degrees Of Freedom (DOF): Refers to vibration with energy along three orthogonal translations and three rotations simultaneously

Grms: Grms is used to define the overall acceleration level of random vibration. Grms (root-mean-square) is the square root of the area under the PSD curve. More information about random vibration can be found in our blog article Sinusoidal and Random Vibration Testing Primer.

HALT Operational Limit: The stress level prior to where a product does not operate properly, but will return to correct operation if the stress level is reduced. Improper operation can be an out of specification condition. HALT is performed to determine the Operational Limits for low temperature, high temperature, vibration, and combined temperature and vibration.

HALT Destruct Limit: The stress level at which the unit becomes inoperable and will not return to correct operation if the stress level is reduced. HALT Destruct Limits are determined for low temperature, high temperature, vibration, and combined temperature and vibration.

Some Facts and Misconceptions about Highly Accelerated Life Testing

• Producing failures is the goal of HALT testing. The user should not necessarily focus on what level of stress caused the problem, but should focus on improving the weak points in their product.
• By applying an effective HALT procedure, the HALT Operational Limit and HALT Destruct Limit of the products under test can be found.
• The stress levels in HALT are typically far beyond those experienced by the product in its normal operating environment. These higher-than-normal stresses accelerate the time to failure and precipitate defects more rapidly than under actual service conditions.
• The product under test is in operation during HALT and is continuously monitored for operational failures.
• As stress-induced failures occur, the cause shall be determined, and if possible, the component should be repaired so that the test can continue to find other weaknesses.
• Stresses shall be increased until the practical limits of the test parameters have been reached or the fundamental limit of technology has been reached. Examples of practical limits include the melting temperature of solder joints or excessive softening of plastics. The fundamental limit of technology means that the limits of present day knowledge have been reached. An example of this would be that it would cost an unreasonable amount of effort and money to improve existing battery technology.
• One common misconception is that an abundance of failures will occur during every HALT. Numerous failures may occur, but a large quantity of failures is not likely unless the product is very different than any manufactured before. Successful companies produce pretty good products; otherwise they would be out of business. However there may be a weakness or two in a new product that could create early failures resulting in large warranty costs. These weaknesses should be found in a properly run HALT test.
• HALT is a qualitative test with the goal being to expose design weaknesses. It is very difficult to demonstrate a service life or a mean time between failures (MTBF) using HALT. Other reliability methods may be a better fit to predict an MTBF or service life.

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These repeated temperature changes can result in thermal fatigue and lead to eventual failure after many thermal cycles. Accelerated life testing can be performed by cycling the product to high and low temperatures that exceed its normal use temperatures.

It should be noted that temperature cycling may also be referred to as thermal cycling or thermal shock testing.  However, some test standards, such as MIL-STD-883, make the distinction between temperature cycling being performed as air to air testing and thermal shock being performed with the samples transferred between liquids. This article deals with testing performed using an air to air thermal cycle chamber.

Typical temperature cycling equipment consists of at least one hot chamber and one cold chamber. The test samples are automatically transferred between the two chambers by an elevator-type mechanism. It is also possible to perform temperature cycling in a single compartment chamber where the temperature is ramped between hot and cold. This generally produces a slower rate of temperature change compared to the two chamber method.

The acceleration factor resulting from the temperature cycle test is the ratio of the product life at normal operating conditions to the life at accelerated test conditions and is given by the Coffin-Manson equation:

AF = (ΔT _test / ΔT _use) ^m

                        AF = Acceleration Factor

ΔT _test = Test temperature difference (°C)

ΔT _use = Use temperature difference (°C)

m = Fatigue or Coffin-Manson exponent

As an example, assume a product that undergoes 5 daily temperature transitions from
20 °C to 60 °C (ΔT _use = 40 °C) while it is normally being used. The following acceleration will occur if the product is temperature cycle tested using a high temperature of 100 °C and a low temperature of -20 °C (ΔT _test = 120 °C), assuming a typical Coffin-Manson exponent of 3:

AF = (120 / 40)³ =27

Testing this product for 1000 temperature cycles using the accelerated conditions would therefore be equal to 15 years of life based on the stated use conditions.

(27 X 1000 cycles) / ((5 cycles per day) (365 days per year)) = 14.8 years

However, care must be taken when choosing the test conditions so that both the upper and lower temperatures used do not exceed the temperature limits of the product. Doing so can result in failure modes that would not occur during normal operating conditions.

The rate of change between the cold and hot temperatures should also be controlled. Some specifications require that the test specimen reaches the dwell temperature within a given time limit for each change in temperature.

The proper dwell time at temperature extreme must also be considered. In general, the time must be long enough to allow the part to equilibrate to the air temperature. Larger and heavier parts with a higher thermal mass will therefore need longer dwell times than lighter and smaller parts with less thermal mass.

It is also important not to remain at the dwell temperatures for too long of a time, as this can also result in invalid failure modes. An example of this would be solder creep failure in a circuit board that is soaked for too long of a time at a temperature too close to the melting point of the solder.

Knowing the correct value for the fatigue or Coffin-Manson exponent is also important, as small changes in this exponent can have larger changes in the acceleration factor. Exponents for many materials have been reported, and can be found in the literature or on the Internet. It is also possible to experimentally determine the fatigue exponent by performing multiple tests with different values of ΔT _test.

Delserro Engineering Solutions, Inc. (DES) has many years of experience performing temperature cycle testing and can assist customers in setting up a test using the proper test conditions and correlating the results to time in the field.

So if you don’t know what test conditions you should use, what specification to choose, or how to correlate your test to field life, we can help you, because we are reliability testing experts!

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To keep up with increasing vibration and shock testing demand, DES added a brand new Unholtz-Dickie Electro Dynamic (ED) Shaker Test System. The shaker is a model SAI30F-S452/ST system with slip table to perform vibration and shock testing along 3 axes. This gives DES additional vibration and shock testing capability and also will help us turn your projects around faster.

The Unholtz-Dickie SAI30F-S452/ST specifications are:

• 6,000 lbf sine force
• 5,500 lbf random force
• 100G peak vibration acceleration
• 200G peak shock acceleration
• 1 to 3,000 Hz frequency range
• 2 inch stroke
• Vibration: Sine, Random, Sine on Random, Random on Random
• Replication of measured field data
• Gunfire vibration

DES can perform the most complicated shock and vibration test projects with our:

• Two (2) ED Shaker vibration and shock test systems
• Two (2) AGREE temperature cycling chambers to perform combined vibration and temperature testing.
• State of the art controllers
• Many high speed data acquisition channels

What sets us apart from other labs is our in depth experience and technical capability to understand and reproduce the most complicated vibration profiles. We also continually invest in new, high-quality equipment to ensure that vibration and shock testing are as accurate as possible. We have performed vibration and shock test on complex products used in automotive manufacture, space applications, rocketry, and medical and military environments.

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DES was awarded multiple contracts to perform combined temperature and vibration reliability testing of Mass Air Flow Sensors from various automotive part manufacturers and from a major auto parts supplier.

The applicable test specification was GMW 3172, a General Motors Specification for electronic component durability.  The test requirements in GMW 3172 were 13 Grms random vibration from 10 to 2000 Hz.  Simultaneously with the vibration testing, DES’s AGREE Chamber subjected the MAFS’s to temperature cycles between -40 °C and +125 °C.  In addition to the harsh temperature and vibration environment, the sensors were electrically powered and monitored for operation or failure during the test.  These harsh conditions had to be run for at least 44 continuous hours per axis along three different axes.  Sometimes they were run for longer durations.  Many sensors were tested simultaneously which added to the challenge.  Finally, a bench air flow tester was used to perform calibrated air flow measurements after each axis to verify the electrical output of each sensor.

This case study shows the advanced capabilities of DES to complete the most difficult temperature and vibration test projects.

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The goal of this article was to teach product developers how to get the most bang for their testing buck; a goal that aligns perfectly with DES’s philosophy. No matter what your testing needs are, be they HALT, HASS, or other environmental or stress tests, DES is able to help you design and implement the most comprehensive and accurate test possible. As always, our client’s success is the source of our satisfaction.

Showing Our Advanced Testing Capabilities

The article highlighted DES’s advanced capabilities when it comes to designing complex testing equipment. In this instance, the devices being tested were a series of proposed new sensors for car engines. For this test series, the testing fixture was incredibly complicated and the testing included combined temperature, vibration, and electrical loads, a perfect fit for DES’s vibration shaker chamber.

When you need a HALT or HASS test, or any other testing services, DES has you covered. Our engineers have more than 60 years of combined successful engineering experience. We specialize in stress, reliability, durability, vibration, shock, highly accelerated life testing (HALT), highly accelerated stress screening (HASS), accelerated life testing, and environmental testing. When done correctly, these tests can help you save money, cut production time, and increase product reliability.

Helping Save on Production Costs

The article closed with a few tips from DES and other testing engineers on how they can form the best working relationship with a reliability testing facility. Appropriate communication was the top recommendation. However, there are a host of tips in the full article on getting the most out of your product test.

To read the full article, visit Desktop Engineering. If you’re interested in running a test, contact Delserro Engineering Solutions.

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Highly Accelerated Life Testing Procedures

Speeding up the process of device or circuit failure requires extreme inputs, those that are unlikely to occur during real-world use by customers regardless of the environment. Three common testing inputs are high and low temperatures, rapid cycling of the same and vibration along six-axes. In some cases, a highly accelerated life test (HALT) will incorporate combined temperature and vibration stresses. These inputs can result in component failure in the span of days, hours, or even minutes compared to months or years of typical usage.

Benefits of HALT Testing

While the percentages of failure based on the stress applied to a product can vary significantly, highly accelerated life testing can typically expose weaknesses faster than other means of testing. For example, of the above inputs, roughly two-thirds of failures will only come after the introduction of vibration alone or combined vibration and temperature tests. This means that during the product development process, a significant number of potential flaws would not be identified through testing that did not include these two stresses.

Just as important, many of the failures highlighted during a HALT test arise from design problems that are relatively easy to remedy. With thermal-based malfunctions, engineers may find that the issues come from materials with vastly different rates of thermal expansion, or deficient leads or crimps. Other problems can come from flaws in the design of the printed circuit boards.

Combined vibration and temperature during HALT testing can also identify issues related to poorly soldered joints and leads. However, failures during vibration may also be caused by fretting, as well as occurring from adjacent parts coming into contact. These design flaws are relatively simple to identify, such as wires rubbing against PCBs or other sharp-edged portions of the system, and arise regularly during the vibration phase of a HALT test.

As a result of the HALT test uncovering these issues early in the process, or soon after the prototype phase, there is the ability to make relatively small changes in design or production. Companies can also identify parts that may not last even during the warranty period in the fraction of the time it might take to find out during normal lifetime testing. As a result, some clients have been able to save a great deal on their product development costs by identifying part and component weaknesses long before the production process.

Some Facts and Misconceptions about Highly Accelerated Life Testing

• Producing failures is the goal of HALT testing. The user should not necessarily focus on what level of stress caused the problem, but should focus on improving the weak points in their product.
• By applying a sequence of stepped low-temperature soaks, high-temperature soaks, rapid temperature transitions, high G random vibrations, and combinations of these testing modes, the HALT Operational Limit and HALT Destruct Limit of the products under test can be determined.
• The stress levels in HALT are typically far beyond those experienced by the product in its normal operating environment. These higher-than-normal stresses accelerate the time to failure and precipitate defects more rapidly than under actual service conditions.
• The unit is in operation during the testing program and is continuously monitored for operational failures.
• As stress-induced failures occur, the cause shall be determined, and if possible, the component should be repaired so that the testing program can continue.
• Stresses shall be increased until the practical limits of the test parameters have been reached. Examples of practical limits include the melting temperature of solder joints or excessive softening of plastics.
• One common misconception is that an abundance of failures will occur during every HALT. Numerous failures will typically occur, but a large quantity of failures is not likely unless the product is very different than any manufactured before. Successful companies produce pretty good products; otherwise they would be out of business. However there may be a weakness or two in a new product that could create early failures resulting in large warranty costs. These weaknesses should be found in a properly run HALT test.
• HALT is a qualitative test with the goal being to expose design weaknesses. The HALT will not demonstrate a service life or a mean time between failures (MTBF). Other reliability methods may be a better fit to predict an MTBF or service life.

Contact DE Solutions

Delserro Engineering Solutions provides a variety of testing services, not the least of which is highly accelerated life testing (HALT). However, we can also test products in a variety of environments such as vibration, shock, and climatic. We can also design custom reliability test procedures.

If you are looking to find weak points in a design through testing, please contact us for a plan that best suits your needs. Fill out the short contact form at the link above or call us at (610) 253-6637 for a review of your needs. We look forward to working with you to maximize the return on your testing and design investments.

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