RJ45 CONNECTORS: SOLID OR STRANDED?
You’re probably familiar with the ubiquitous RJ45 connectors: it’s the little plug on the end of cables that help connect you to the Internet. Fast fact: their actual name is “8P8C” (for 8 position, 8 connectors) and it is universally called “RJ45” based on phone line standards. They come in more than one style and before you decide on which one to use, it's a good idea to understand what type of network cable you're going to be terminating. It’s important to note that if you're in the market for RJ45 plugs, then that means you'll be using them with twisted-pair network cable. Depending on if that cable is rated Cat3, Cat5, Cat5e or Cat6, it's going to be classified as either solid or stranded.
What does "solid" mean?
“Solid” describes cabling with conductors made of solid metal, usually copper. With each conductor made of a single thick copper wire, the cable is generally more rigid. Since that makes it somewhat resistant to bending, solid cable is most often used in backbone cable runs through walls and conduit, where flexibility isn't really necessary.
What does "stranded" mean?
Stranded cables are made up of many fine metal filaments, which are twisted together to form the larger, thicker wire. Since it is composed of thin wires, stranded cable is a lot more flexible than solid, so it's commonly used in patch cords and other shorter network cables that need to be able to flex and bend during use.
CHOOSING THE RIGHT RJ45 CONNECTOR
So, what does all this mean for your RJ45 connectors? Well, once you understand which type of cable you're dealing with, choosing the right plug suddenly becomes easier. It's basically just a matter of matching cable type to connector type: solid goes with solid — and stranded goes with stranded. Just be sure not to mix and match the two, or you'll end up with a bad connection.
It's also very important to note that some RJ45 connectors offer solid AND stranded compatibility, but it will typically be one or the other.
Why aren't all RJ45's the same?
They are not because in order to make a successful connection, a plug's tooth-like contact pins need to properly pierce through the plastic insulation of the accompanying wire. When this is done correctly, the pin can physically touch the wire conductor and a connection is made. It's a simple concept to understand, but because of the differences between solid and stranded wire, the insulation-piercing process is a little different for each type.
While solid RJ45 teeth only need to make contact with one wire, stranded RJ45 teeth need to work their way in among multiple strands, in order to make a worthwhile connection. The subtle differences between connector contacts can be tough for the untrained eye to identify but can cause some big problems when paired with the wrong type of cable. Save yourself time, frustration and wasted supplies by verifying that your cable and RJ45 connectors "match."
HOW DO YOU DIFFERENTIATE A SOLID OR STRANDED RJ45 PLUG?
Let’s say you have a connector and aren't sure if it's stranded or solid. You may be wondering if there is some way to visually confirm which one it is. There is.
We really must stress that the best way to ensure a correct connection is to know which type of RJ45 and cable you have before making the connection. However, if you've got an RJ45 and you're not sure if it's solid or stranded, there are some methods that could help you figure it out.
Here's how it's done: if you look at the plug from the side, you'll see the tiny metal connector pins. Those pins are tasked with piercing the cable jacket and contact on the copper wire. On these pins you'll see little “teeth” that do the poking and then contact the metal, in order to make a conductive connection. Typically, a solid only plug will have longer, staggered teeth. They will be more widely spaced from each other, since they are only focused on straddling a single, relatively thick wire.
A stranded connector, on the other hand, may have numerous teeth and may be spaced closer together, with their job to get up and in between the stranded filaments. If the teeth are spaced, the space between is usually shallower. Their job isn't really to straddle the filaments, since piercing the jacket and getting between the strands will make the necessary connection.