Design Considerations for High Voltage Cable Assemblies

Whether you are looking for off-the-shelf medical connectors or designing a custom connector for your device, there are important considerations to keep in mind. Medical device engineers must make certain they meet, if not exceed, specific standards to ensure product performance, durability, and patient and user safety.

At Amphenol Alden, we provide the best connectors to medical device companies all across the world, and we are proud of the reputation we’ve developed for providing creative solutions to our customers’ problems. Our attention to detail and expertise is part of what brings our OEM partners back again and again for new projects.  

That is why in today’s blog post, we are presenting design considerations for high voltage cable assemblies

What is a High Voltage Interconnect?

Generally speaking, a cable assembly or connector would be considered a high voltage product if the minimum operating voltage is at or above 1kVDC. While the vast majority of medical device cable assemblies and connectors operate at lower voltages (ranging from millivolts to 300VDC), some require much higher operating voltages to function properly. X-ray machines require very high operating voltages (up to 75kVDC) to create the X-ray energy which is used to image a patient. Other products, such as those related to surgery for ophthalmology or oncology, use YAG (Yttrium Aluminum Garnet) lasers which also require high operating voltages.

Top Design Considerations

What are the top design considerations that should be taken into account for high voltage (HV) cable assemblies? They are actually quite similar to those for lower voltage applications and include consideration of electrical characteristics, mechanical performance requirements, operating environments, and others.  

To begin, understanding the operating environment and voltage characteristics (i.e., nominal and peak operating voltage, duty cycle, breakdown voltage, etc.) is necessary when considering the design of HV cable assemblies. These parameters directly influence the materials, shape, and termination techniques chosen for your high voltage cable assembly. For example, will the HV cable assemblies be used in conjunction with dielectric oil or not? Dielectric oil is great for increasing electrical breakdown voltages between adjacent connectors (i.e., Dielectric Withstand Voltage, a.k.a. DWV) but requires accommodation for certain sealing features. In an open-air environment, adjacent contacts and connectors must be spaced further apart (relative to HV connectors designed for use in dielectric oil) to achieve the same DWV value to protect against unintended electrical arcing (i.e., electrical breakdown to ground). Ensuring appropriate DWV requirements are met is critical to ensuring the safety of the patient and caregiver around high voltage energy. 

In the world of high voltage cable assemblies and connectors, smaller interconnects = better when designing for high voltage applications. Traditional high voltage interconnects are large connectors, their size being a function of creepage and clearance requirements associated with HV products. At Amphenol Alden, our long history of product innovation with high voltage interconnects allows our cable assemblies and connectors to be smaller than products offered elsewhere (all voltages being equal). By tweaking the geometry of our connectors, we can attain greater DWV targets while shrinking the size of our product.

Common Applications For High Voltage Interconnects

Applications for high voltage interconnects cover a broad range of products, from imaging to therapy and monitoring; they are used in different ways. Imaging products, such as X-ray and CT machines, require the highest operating voltages in application, as the high voltage energy is used to create the X-rays that image a patient. Therapeutic applications, such as YAG lasers used to correct cataracts require high voltages, ranging from 5-10kvDC, which is not as high as the imaging products. Defibrillation equipment, arguably the most frequent user of high voltage energy, uses the energy pulse to restart the heart when a patient goes into cardiac arrest. 

Conversely, some products such as patient monitoring devices may require protection from high voltage ensure the safety of the equipment. When a patient requires defibrillation while connected to a monitoring device, there may not be time to remove the leads between the patient and the device before applying the defibrillation energy. As such, some monitoring equipment is designed with safeguards that absorb, or otherwise dissipate, any energy which might travel through the leads towards the device during defibrillation. These examples are just a few of the types of medical applications requiring high voltage interconnects.

Benefits of Working With Amphenol Alden

Teaming up with Amphenol Alden provides a host of benefits, such as:

  • Dependability. Customers know they can depend on the team at Amphenol Alden for all their medical interconnect needs, from custom-made solutions to our comprehensive catalog of standard products.
  • Expertise. We have more than 40 years of experience developing medical cable assemblies and connectors for our customers.
  • Responsiveness. If you have questions about a particular off-the-shelf or customized part, our medical interconnect experts are here to walk you through the process of selecting a standard product or customizing a unique medical cable assembly or connector.

Partnering With Medical Industry Experts for High Voltage Projects

At Amphenol Alden, our engineers have years of experience designing connectors for use in high voltage applications. To learn more about our standard catalog of high voltage connectors and cable assemblies, please contact us today!