At DES, we have tested many different kinds of products ranging from medical devices to aerospace products. We have performed numerous reliability tests and developed numerous accelerated life test plans. Many times, our customers ask us, “How do we make our products more reliable?” There are analytical methods and processes that can be used to improve product reliability. However, the focus of this article will be How To Make Your Product More Reliable Through Testing.
DES president Gary Delserro is featured in an article published in Assembly Magazine on July 9, 2021. Titled “Accelerated Life Testing,” the article discusses different types of manufacturing life testing and quotes Gary with reference to highly accelerated life testing (HALT):
“Companies have reported savings in the millions after using HALT,” claims Delserro. “The test can accelerate a product’s aging process from actual months into test minutes, and it can help you discover weaknesses in your product during the design stage. Combined vibration, temperature and electrical stress variables, as well as internal fluid pressure, are typically used during HALT to induce failures and uncover fault points. By using combinations of loads, we can uncover design or manufacturing process flaws before they reach your customer.”
A customer approached DES looking to perform Highly Accelerated Life Testing (HALT) on a new circuit board design. DES and the customer agreed to test the circuit boards using DES’s traditional HALT test procedure which calls for hot/cold temperature steps followed by rapid temperature ramping, vibration steps and combined temperature and vibration stresses. HALT testing on electrical componentry is quite common across industry to expose design weaknesses; both mechanical and electrical (What is HALT and Why Perform HALT?). Typical failures include poor solder connections, overheating, component failure, etc. (What Kind Of Failures Occur During HALT?)
Continue reading Circuit Board HALT Testing Case Study →
Rapid Highly Accelerated Life Testing or Rapid HALT is a reliability test method that is used to expose product weaknesses. A Rapid HALT procedure is a modification of a Classical HALT procedure. For more information about Classical HALT procedures, refer to the following blog articles:
A Rapid HALT is an abbreviated HALT, typically one day of tests, making it a great cost-effective solution for those seeking faster qualitative results. Exposing a product to a Rapid HALT early in the design process can help reduce product development time and cost by enabling manufacturers to identify flaws or areas of improvement before it’s too late.
Rapid HALT’s are a good tool for assessing the reliability of different suppliers of components but can also be used to assess the reliability of less complicated products. For example, DES has performed Rapid HALT’s to evaluate the reliability of different suppliers of power supplies, cooling fans, and LED’s. DES has also performed a Rapid HALT to study different fastening methods in order to determine which was more robust.
Figure 1. DES Rapid HALT Profile
Continue reading Rapid HALT – A Cost Effective Alternative to HALT →
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.
Continue reading Cooling Fan Reliability Testing Case Study →
Product failures in HALT testing are defined as either the cessation of any functions or an out-of-specification condition for any performance characteristic. When a failure occurs, it is documented in DES’s HALT log. The exact time and test condition when each failure occurred is noted.
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
Figure 1 – Failure of Improperly Designed Mounting Tabs
Continue reading What Kind Of Failures Occur During HALT? →
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.
Continue reading What Equipment Is Used For HALT? →
HALT procedures vary from lab to lab but are typically performed similar to DES’s procedure which is summarized below. DES’s HALT procedure is divided into 5 Stages: Stage 1 – Temperature Step Stresses, Stage 2 – Temperature Ramps, Stage 3 – Vibration Step Stresses, Stage 4 – Combined Temperature &Vibration Stresses, and Stage 5 – Temperature Destruct Limits.
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)
Figure 1 – Stage 1 Temperature Steps
Continue reading What Is A Typical HALT Procedure? →
Highly Accelerated Life Testing (HALT) is a rigorous reliability test method that is used to expose product weaknesses. The goal of HALT is to proactively find weaknesses and fix them, thereby increasing product reliability. Because of its accelerated nature, HALT is typically faster and less expensive than traditional testing techniques.
HALT of circuit boards in one of DES’s HALT chambers
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.
Continue reading What Is HALT (Highly Accelerated Life Testing) And Why Perform HALT? →
Delserro Engineering Solutions (DES) was honored to be featured in a recent article discussing the capabilities of engineering testing companies. The article highlighted the benefits, in terms of both design and cost, of adequately testing designs, preferably as early in the process as possible. It also discussed the ins and outs of partnering effectively with a reliability testing facility.
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.
Continue reading Delserro Engineering Solutions Featured in Desktop Engineering →
