At first glance, all RJ-45 connectors look the same, regardless of category. However, in practice, there are significant design differences between them that affect connection quality, cable compatibility, and network signal stability.
In this article, I have compared RJ-45 connectors of three categories: Cat 5e, Cat 6 and Cat 6A in detail, paying attention to the internal structure, the presence of guide inserts (load bar), the location of holes for conductors, and the features of crimping – especially when using thick shielded cables of the F/FTP type. I have accompanied all this with real photos and examples from my own experience.
What is the difference between 5e, 6 and 6A connectors
At first glance, all these RJ-45 connectors may seem the same, but there are important technical differences between them. The difference between category 5e, 6 and 6A connectors is not in the dimensions of the housing, but in the internal geometry of the holes, the diameter of the conductor channels, the accuracy of core positioning and the ability to work with thicker, stiffer cores (especially for shielded cables). I will give a small comparison table:
| Category | Wire Hole | Description |
|---|---|---|
| Cat 5e | ~1.0–1.05 mm | Accommodates AWG 24 (0.51 mm) or smaller. |
| Cat 6 | ~1.1–1.15 mm | Accommodates AWG 23–24. Holes are slightly larger to accommodate stiffer and thicker conductors. |
| Cat 6A | ~1.2–1.35 mm | Accommodates AWG 22–23. Has larger holes for insulation of each wire, more accurate positioning due to the through-insert |
If we consider the Cat 5e category, the holes are arranged in one row. However, with the increase in the number of holes, there is less physical space in the connector, and if we consider the Cat 6 connector, the holes are arranged in a staggered pattern. In the Cat 6A connector, the internal membrane between the holes has been removed altogether, for this purpose an additional guide insert is usually included with the connector.
While the inside of Cat 5e and Cat 6 connectors have so-called guides, the Cat 6A connector has an empty space designed for a special guide insert.
Load bar presence
A load bar is a small plastic or sometimes metal insert through which individual cable cores are passed before inserting them into the connector itself. It serves to:
- make installation easier, especially with rigid AWG 22–23 cores.
- precisely align and position the cores;
- reduce the impact of crosstalk (NEXT, AXT), especially in high-frequency Cat 6A;
Usually such bars come with connectors. I bought Vention IDFR0-50 connectors, which came with a package of these inserts
If you look at the overall crimping plan, it becomes clear how thick the conductors are, and how this insert facilitates the overall switching process, especially when it comes to thick shielded Ethernet cable.
Crimping a Cat 6A connector
Crimping a Cat 6A connector is almost the same as its predecessors, except that the wires must first be fed through the guide insert, cut off the excess, and then insert the insert into the connector and crimp.
If the cable is shielded, the foil that acts as the shield must be turned out and the connector inserted so that its metal body is in contact with this foil. Only in this case will the shielding work.
Remember that the thickness of the conductors of a Cat 6a cable will not fit into a Cat 6 connector, so consider this when purchasing.
Conclusions
In conclusion, although RJ-45 connectors of all three categories – Cat 5e, Cat 6 and Cat 6A – have the same shape and external dimensions, their internal design is significantly different. These differences become especially noticeable when working with thick or shielded cables. Cat 6A is no longer just an improved version of previous categories, but a separate, more complex to implement system with clear requirements for installation accuracy, conductor geometry and shielding compliance. The presence of a guide insert (load bar) in the kit greatly simplifies crimping and allows you to achieve a stable, reliable connection. When choosing a connector, it is important not only to focus on the category, but also to take into account the type of cable, its thickness, the presence of a shield and compatibility with a specific connector design. This approach avoids problems during installation and ensures high-quality network connection.
In the next article, I will show the complete step-by-step process of crimping a Cat 6A connector with photos, recommendations and typical mistakes. Don’t miss it!
