Surge testing is a critical step in the product development of power supplies across all industries. It ensures they can withstand sudden voltage spikes and power surges in real-world environments without failing or degrading performance.
As the heart of electronic systems, power supplies must provide clean, uninterrupted power even during electrical disturbances like lightning strikes, load-switching transients, and electrostatic discharge. Surge testing is even more vital for mission-critical applications where reliability is paramount, such as military systems.
In this article, we’ll cover surge testing, why it’s crucial to a product, and how to test a power supply for power surges to ensure it can withstand a real-world surge.
Surge testing involves subjecting a power supply to short-duration, high-energy electrical pulses using a surge generator to simulate the voltage spikes and power surges that can occur in real-world operating environments.
The international standard IEC 61000-4-5 defines the waveforms used for surge testing. A typical surge pulse has a 1.2×50 microsecond voltage waveform and an 8×20 microsecond current waveform, meaning the voltage reaches its peak in 1.2 microseconds and decays to half that value in 50 microseconds while the current reaches its peak in 8 microseconds and decays to half that value in 20 microseconds.
To understand the meaning of surge power, it’s important to distinguish between its magnitude and duration. Surge magnitude refers to the peak voltage level, which can range from a few hundred volts to several kilovolts depending on the cause and location of the surge. Surge duration is the period over which voltage remains elevated above its normal level, typically lasting only microseconds or milliseconds.
Standardized surge pulses are applied between different power and signal ports on the device under test (DUT) during a surge test. The peak voltage, number of pulses, and time between pulses are specified based on the installation class and test level for the intended application.
Surge testing is a critical part of developing and validating power supplies for various applications, from consumer electronics to mission-critical systems.
One primary reason for surge testing power supplies is to ensure they will operate reliably in harsh environments. This certainty is especially crucial in military applications, where power supplies are subjected to extreme environmental and electrical conditions not seen in typical commercial settings. Surge testing provides assurance that power supplies can handle a worst-case scenario power surge, meaning they will not fail or experience performance degradation.
In some applications, a user may manually reset a device after a surge event if a system has shut down. However, this is usually not allowed for mission-critical systems, which must continue operating error-free during the entire event. Surge testing helps validate that power supplies can maintain the performance of these critical systems even during severe electrical transients.
Transient voltage suppressor (TVS) devices, metal oxide varistors (MOVs), and other surge protection components are critical for power supplies. However, these parts must be properly designed and incorporated into the circuitry. Surge testing allows engineers to validate that surge protection circuits are robust and will effectively clamp and divert surge energy as intended.
Surge-related failures in the field can be costly in terms of equipment damage and operational downtime. A power supply failure can render critical systems inoperable and compromise productivity or safety. Manufacturers can catch and correct potential issues by conducting a surge test before deploying power supplies, greatly reducing the risk of surge-induced field failures.
Many industries have specific standards and requirements for power supply performance, including the ability to withstand surges. Surge testing is crucial for demonstrating compliance with these standards and ensuring the power supply is suitable for its intended application.
Power supplies often serve as the first line of defense against surges for the sensitive electronic components they power. Proper surge testing ensures that the power supply can effectively absorb and dissipate surge energy, protecting downstream electronics from damage.
Conducting a surge test during product development can help manufacturers and engineers identify and address potential issues early on, resulting in a more robust and reliable final product. This enhanced reliability can lead to improved customer satisfaction and reduced warranty claims.
Surge testing typically occurs at several stages in the product development of power supplies, including design validation and possibly safety certification. Here’s a step-by-step guide on how to test a power supply for power surges:
If necessary, make design modifications to improve the power supply’s surge resilience and repeat the testing process until the desired performance is achieved. Remember that a side-to-side surge can cause damage to sensitive electronic components, so proper precautions must be taken during testing. Proper precautions include ensuring the surge close time is set correctly to prevent excessive stress on the power supply and using appropriate isolation and grounding techniques to prevent unintended surge coupling.
Surge testing ensures power supply reliability and performance in harsh environments. At ACT, we understand the critical importance of surge testing in developing and validating power supplies against military standards. With over 40 years of experience in designing and manufacturing highly reliable power conversion solutions, we have the expertise and state-of-the-art facilities to ensure our products withstand the most demanding surge requirements.
Surge testing is a critical part of our product development process, and our power supplies undergo rigorous testing at different stages of development to ensure we provide the reliable, long-term-performance products you need.
Contact us today for military-grade power supply solutions.
