Creating the Perfect Medical Cable
Blogging offers me the freedom to express my opinion. Thinking about what to write about this month, I decided to express my feelings about the “perfect” medical cable. Does such a cable exist? Let’s look at the elements that make up a medical interconnect system.
The plug, which is typically the end that connects to the device, would be as small as possible but not so small that it is difficult to grasp for any potential users. The plug should be shaped so that the user intuitively knows how to connect it to the device. USB plugs have frustrated me for years. Until the symmetrical Type C connector’s advent, I typically tried to insert USB plugs in the wrong orientation most of the time. Because of this, the previous USB Type A, B, Mini-A, and Micro-A connectors were, in my opinion, poorly designed.
Besides connecting intuitively, the plug should mate with the receptacle smoothly and securely. If the connector is a locking type, a secure connection should be obvious either audibly or by tactile feel. If the connector is non-locking, the user should have confidence that it will remain connected when mated.
The perfect medical cable, regardless of the size and number of conductors, would be very flexible. It should be easily coil-wound for storage and not exhibit any memory when uncoiling. Depending upon the application, it may also need to have sufficient tensile strength not to be damaged by normal or even abnormal use.
An ideal medical cable would have a jacket that, subjectively, feels “nice.” It would not be tacky or rough, preferably having a velvet feel. The medical cable jacket would be durable enough to resist cuts or tears, and the color should be dark to reduce the visibility of inevitable scuffs and marks. Depending upon the intended application, the medical cable should withstand repeated cleaning or even sterilization.
That leads us to the strain relief – the component that bridges the plug and the jacket together while providing both aesthetics and mechanical strength to the overall medical assembly. The strain relief should be smooth, not segmented so that the bend relief does not capture biological matter or dirt and is easy to clean. It should bond to the cable jacket, which will improve the assembly’s strength and flex performance.
Many medical cable assemblies require nameplates or markings. If this is the case, printed information should be as large as possible, even if it minimizes the brand logo. Printing on high-quality polycarbonate layered nameplates is much easier to read than markings that are molded into the cable assembly. Printed information that cannot be seen in low light or by those with poor sight is often useless.
RoHS (including RoHS 2, 3, 5/6) and REACH compliance has become necessary, and the perfect cable would be compliant. Gold and tin are two common materials (minerals) that are used in medical cable assemblies. Assuring Conflict Mineral compliance is typically required for cables that are manufactured for a publicly traded company.
Does the perfect medical cable exist? Yes. I have seen examples that exhibit all the positive characteristics that are detailed in this blog. When we worked together, ClearPath Medical CEO Matt Pathmajeyan led the engineering team that developed these unique cables. We established detailed specifications through close collaboration with our customer partners, which led to interconnects that were perfect for the intended medical device application. Most important, is ClearPath Medical’s Design for Manufacturabilty process, which enables them to diligently build consistently reliable medical devices and cable assemblies.
If you would like assistance designing your perfect medical cable, I urge you to contact ClearPath Medical. The team has the experience and expertise to guide you along the path to a perfect cable.
Have more questions, or comments about the use of silicone in medical device and cable assembly applications? Be sure to contact us – we’d love to hear your thoughts!
Hank Mancini
Hank is a cable assembly ambassador and guest author on ClearPath Medical’s blog. He has more than 20 years of experience in manufacturing with a focus on medical devices leading up to his recent retirement. He's passionate about everything medical cable assembly related, along with the Dodgers, Lakers and taking his brood of grandchildren to Disneyland.