When designing a custom cable assembly, one of the earliest and most important decisions you’ll need to make is whether to use flat cables or round cables. While both serve the same fundamental purpose—transmitting power, data, or signals—their structure, performance characteristics, and ideal use cases differ significantly. Choosing the right format is crucial to the success of your project, especially when dealing with high-volume or specialized manufacturing needs.
Understanding the Basics
Round cables are the traditional option, featuring conductors bundled together in a cylindrical shape. The individual wires may be twisted or shielded, and the cable is typically wrapped in one or more layers of insulation and protective jacketing.
Flat cables, on the other hand, consist of conductors arranged side by side on the same horizontal plane. This ribbon-like design makes the cable flatter and more flexible in certain directions, which can offer significant advantages in specific applications.
Advantages of Flat Cables
- Space-Saving Design. Flat cables are ideal for environments where vertical space is limited, such as medical devices, consumer electronics, and compact industrial machinery.
- Improved Flexibility in One Plane. Flat cables bend easily in a single direction, making them perfect for dynamic applications like robotics and moving assemblies that follow predictable motion paths.
- Consistent Electrical Characteristics. Because the conductors are uniformly spaced, flat cables can offer predictable impedance and low crosstalk, especially beneficial in high-speed data or signal applications.
- Simplified Routing. Flat cables are easier to fold, stack, and run in tight spaces, leading to cleaner and more organized installations.
Advantages of Round Cables
Round cables offer several advantages that make them a strong choice for many industrial and large-scale applications. Their bundled structure and protective outer jacket provide superior mechanical strength, making them well-suited for harsh environments and heavy-duty use. They can also support more advanced shielding and insulation, which makes them ideal for longer cable runs and situations where electromagnetic interference (EMI) is a concern. Additionally, their round shape makes them easier to pull through conduits and cable trays, something that’s often required in infrastructure projects. Finally, round cables can handle a higher number of conductors, making them a practical option for complex wiring setups.
When to Choose Flat vs. Round
If you’re working in a tight or compact space, like inside a medical device or a consumer electronics housing, flat cables are often the better choice. They’re also ideal for applications that involve repetitive motion, such as robotics, where the cable needs to flex consistently in a single direction. On the other hand, round cables are preferred for rugged or industrial environments, where durability, longer cable runs, and shielding are priorities. They’re also easier to install in conduits and better suited for projects requiring high conductor counts or advanced EMI protection.
Custom Cable Assemblies at Scale
Whether you need flat ribbon cables for a medical device rollout or round multi-conductor cables for a large-scale industrial build, Quadrangle Products can deliver high-quality, fully customized assemblies to match your exact requirements. We work with clients across industries to design, prototype, and manufacture large orders of custom cable assemblies, built to handle demanding environments and high-volume production needs.
Our engineers will help you evaluate factors such as:
- Flexibility and bend radius
- Signal integrity
- Environmental conditions
- Connector compatibility
- Bulk manufacturing timelines
Talk to the Experts at Quadrangle Products
Need help deciding between flat and round cable designs for your next project? Contact Quadrangle Products today to discuss your specifications. Our team has decades of experience helping OEMs, engineers, and manufacturers source reliable, high-performance custom cables in large volumes.