What is a Wire Vs What is a Cable? from AutomationDirect

Wire and Cables are two necessary, but often overlooked components of every automation system. What are their differences? Why are they used? For today, let’s ignore mechanical or load-bearing types and only focus on the difference as it applies to data communication and electrical power. So what are wires and cables? In simplest terms, a wire consists of one single electrical conductor, while a cable consists of a group of two or more separate conductors. However, these definitions need to be tweaked a little depending on the usage. Even though these definitions are commonly used, there is no one set standard that fits all types of wires and cables. These definitions usually vary based on the organization that regulates them, such as IEEE, NFPA, IEC and UL. The defining characteristics of wires and cables for data communication are similar to those of power transmission, with a few minor differences. First, let’s talk about data. Data wires and cables are designed to carry high frequency signals at low voltage and minimal interference. Here, each connection architecture is regulated separately based on their intended use. Wires are typically defined as a solid or stranded, insulated bundle of conductive material capable of transferring a single electrical signal, like a lead wire connecting a PLCs’ I/O to a device within an enclosure or cabinet. If it can only transmit/receive a single signal at a time, it’s a wire. Cables are then defined as any isolated connection that can send and receive multiple simultaneous transmissions. Usually, this means that any insulated bundle of wires is a cable, but not exclusively. For example, a coaxial cable only has a single conductor, but is a cable because it can transmit a large amount of data using a wide range of frequencies. Similarly, a fiber optic cable is a cable, even though the individual fibers are not wires. The important thing to remember is if it can send or receive multiple signals, it’s a cable. If it’s one signal, it’s a wire. Now let’s move on to Power. Power transmission wires and cables are used to transport an electrical charge to power a device and cover both AC and DC power. They differ in that they are designed to carry higher voltage and offer less impedance than data cables. Just like with data, wires used for power are still a single conductor capable of transferring an electrical signal. The one big difference is that they also include uninsulated wires, seen most often in AC circuit grounding wires. With power, a cable is any isolated connection with two or more conductors. However, there are instances where a single conductor wire is categorized as a cable. When it comes to high voltage, a large gauge insulated single conductor, such as a stranded high heat-rated industrial can be defined as a cable too! For example, the DLO and MTW cables you can find in AutomationDirect’s store are both single-conductor but are still defined as cables by UL. Make sure to check with your project specifications to be sure you are using the right cable for the job. We hope this clears up any confusion over the differences between wires and cables and makes it easier to choose the right types for your next automation project. AutomationDirect has many different types of wires and cables available for almost any power or data connection you may need, ready to ship to you. You can get your wire and cables in bulk, or for cables, you can also specify custom lengths with cut-to-length ordering. Click here to learn more about our cut-to-length options. Click here to see more videos from AutomationDirect.