The Importance of Power Distribution Units in Medical Test Equipment

June 24, 2020 By Sponsored Content

Medical Test Equipment Requirement ConsiderationsThe medical industry faces numerous challenges in designing electronic and software-run devices. Increasingly sophisticated machines demonstrate growing dependency on similarly intricate electronics, driven by rapid technology development and exceptional competition. On top of it all, the Food and Drug Administration (FDA) requires extensive testing before devices are released to market. Advanced Test Equipment is an important tool in overcoming these challenges, streamlining product testing to ensure quality, functionality, and FDA compliance. Automated and Semi-automated test equipment typically include various sensors, control mechanisms, and active subsystems to validate products across a wide range of applications.

When designing test equipment with complex functions or multiple active subassemblies, the delivery and control of power is crucial. This is often accomplished via custom power distribution units (PDUs), which take input power and reliably distribute it to various downstream equipment. But how exactly do you build a test system, and how are PDUs integrated? We will discuss these issues and more to help you understand the role of PDUs in test equipment.

Test Equipment RequirementsOne big consideration with test equipment is power. Automated test system (ATE) power infrastructure is very different from typical power setups. Because test systems consist of many internal components, they require complex power systems to provide controlled, reliable power to each. Some test system requirements and components include the following elements:

Electromagnetic Interference (EMI) FiltersNearly every product, regardless of application or market, is required to comply with EMC regulations. These standards limit the electromagnetic noise a product can inject onto the local power line. Just as the components and functions of a complex test system vary widely, so too does the EMC noise it generates. To ensure EMC compliance and to protect the ATE from any noise already on the line, EMI Filters are standard in test equipment system architecture. EMI Filters, typically located near the power input/output, are easily integrated into custom PDU’s for a streamlined system design.

PDUsEach piece of equipment in a test system requires a certain amount of current at the right voltage level and may require various safety- or functionality-based controls. A test system needs to include a power distribution unit to ensure downstream equipment receive appropriate power. Power distribution units for test systems ensure sufficient energy flows to each component while also protecting equipment from surges, sequencing power provision, and more. A PDU’s internal power outlet possesses a current and a rated voltage, and they are compatible with both direct and alternating currents.

PDUs are integral parts of a testing system due to their capabilities, and custom solutions may include fully integrated primary and secondary power sources. When using a PDU — or any of the other elements listed here — it is essential to create a power layout. This arrangement ensures each part receives the electricity it needs. Bottlenecks created by a lack of power can stall an entire operation if the affected component is integral to the system. Working with an experienced custom PDU supplier such as Astrodyne TDI reduces risks like this as they partner with your engineers to provide a comprehensive design.

Uninterruptible Power Supply (UPS)Testing can also be affected by power losses, brownouts, and malfunctions during normal operations. The uninterruptible power supply protects against this. UPSs ensure critical components in the system get continuous energy when the power supply encounters a problem. For example, cooling, control, and monitoring systems are crucial to maintaining function during brownouts, as failure can prevent quick recovery or damage equipment.

PDUs and UPSs work together to ensure a testing device receives the energy it requires without the risk of failure. When necessary, UPSs combined with power converters enable you to condition standard electricity to meet the system’s needs. Ultimately, however, it may be easier to use ATE with a global input voltage to bypass the need for a power converter. Be sure to install and apply a UPS to such vital test equipment to keep your systems running as effectively and efficiently as they should.

Emergency Power Off (EPO) FunctionalityAs the role of automated test equipment grows, safety control feature implementations take on new dimension as well. One ubiquitous feature shared by nearly all modern test equipment is Emergency Power Off (EPO) functionality. EPO features simplify reactions to local emergency situations by directly inhibiting power switching and triggering shut down procedures.

GroundingGrounding is another crucial aspect of automated test equipment requirement, both for safety and measurement quality. Grounding secures the safety of operators and equipment by ensuring that all system equipment has a proper path for current to flow to the ground. Quality grounding also includes assurances that electrical connections to the ground are direct, which minimizes the production of radio frequency emissions that can interfere with measurement equipment.

With so many options available, it can be challenging to determine the most effective approach. There are infinite configurations of test equipment parts and features, but they share a common test system power infrastructure. If you are interested in a custom power distribution solution for test equipment or want to learn more about the applications of PDUs, contact Astrodyne TDI today. With over 60 years of experience designing custom power solutions, their team is happy to help you answer these questions.