Manufacturers of electrical and electronic equipment must write and maintain their own internal product test specifications. Test specifications must be developed to test products during the design process before they are manufactured. They must also be developed for original equipment manufacturer (OEM) products that a manufacturer may choose to integrate into their products. Regardless of where equipment design originated, the company whose name is on the box must be sure it will survive in its intended electrical environment.
Because electrical environments in customer facilities are becoming more energetic with electrical disturbances, ensuring that an equipment design is ready for prime-time has become more difficult. Another issue that is causing manufacturers more problems regarding premature failures is the digital nature of today's electronic equipment. As compared to all analog equipment, electronic equipment using digital circuits (i.e., microcircuits) is orders of magnitude more susceptible to common every day electrical disturbances. Disturbances that are even below the clamping voltage for the front-end surge protective devices (SPDs) can easily enter sensitive circuitry and cause permanent damaged.
Electrotek's vast experience in understanding, identifying, solving and preventing (UISP) power quality problems at the grid, facility and equipment level have placed us years ahead of developing the technology to help manufacturers ensure they can manage their power quality at whatever level is required to maintain their bottom lines. Electrotek's largest database of power quality disturbances in the world allows us to use smart algorithms to select the disturbances known to be the most threatening to electronic equipment.
Waveforms from our Power Quality Digital Disturbance Library (PQDDL) are pre-selected and loaded into a programmable disturbance generator and injected into the equipment's power input. Test results from a host of products from one manufacturer, sometimes of similar design relative to the electronic power supply, are then used to determine the most appropriate disturbances and other critical electrical conditions to include in the product test specification. When some aspect (e.g., line voltage, load, internal electronics, etc.) of a design changes, the test is repeated to determine if the level of power quality immunity specific to that equipment design is still acceptable. If changes are needed in the test specification, then design is again evaluated for new sensitivities and sensitivities which have shifted. Then, disturbances with the right energy and frequencies known to cause malfunctions and failures are then added to the specification.
Critical data such as test level, sensitivity frequencies, duplication of expected field conditions and rate of disturbance injection among other data is specified in the test specification document along with examples of some specific disturbances known to cause malfunctions and failures with the specific equipment design.
If a manufacturer doesn't have a test specification or needs to do a better job regarding power quality immunity testing, expert Electrotek PQ engineers are available to help. Our broad experience with manufacturers speaks for itself. Our work is constantly changing the face of electrical and electronic equipment designs.