How to Crimp RJ45 Connectors?

When running network patch cable through a home, it’s more cost-effective to use bulk cable and terminate the ends by yourselves. Because this offers users the flexibility to cut out a required length, whether very short or very long. On the other hand, if one needs to route 50ft Ethernet cable upstairs through a closet ceiling, it’s much easier to run a copper cable without the heads attached, and crimp the ends immediately when it’s in place. Thus, it’s necessary to take a few minutes to learn Ethernet cable crimping. Here uses RJ45 Cat5e cable as an example to show the cable crimping steps.

Prepare the Tools and Materials

Before starting, make sure the necessary crimping tools and materials are prepared. As figure 1 shows, here needs:

Figure 1: Tools of crimping Cat5e cable.

• A length of uncrimped, unshielded Cat5e bulk cable. You can buy it in bulk online, or if there are some Cat5e network cables with damaged connectors on hand, snip them off and start anew. Cat5e color comes in a wide range, the most commonly used is blue. Choose one color you like.
• Cat5e RJ45 UTP modular plugs. They are the plugs at the two ends of a Cat5e cable. Then confirm the wire channels of the connectors can be coupled with the Cat5e cable’s outside diameter (24AWG-0.95mm, 26AWG-0.9mm, 28AWG-0.75mm ).
• A stripper tool and a crimping tool. Stripper tool is used to strip the sheath of Ethernet cable, and crimping tool is for affixing an RJ45 modular plug to the end of a copper patch cable.

In addition, you may prepare a cable tester to test whether the Cat5e cable works properly after crimping both ends.

Steps of Crimping RJ45 Cat5e Cable

The following are the steps of crimping Cat5e cable.

Step One: Cut the Cat5e patch cable to the required length. And use the stripper tool to strip about 2.5cm of the jacket at the two ends of Rj45 Cat5e cable.

Figure 2: Striping the cable.

Step Two: When the jacket stripped, there will be four twisted pairs of wires exposed. Each pair is represented by a solid color and a striped color, including orange-white striped and solid orange, green-white striped and solid green, blue-white striped and solid blue, brown-white strip and solid brown. Separate these pairs.

Figure 3: Four twisted pairs.

Step Three: Choose on wiring standard. T568A and T568B are the two color codes for wiring 8-position modular plug. As the following figure shows, the only difference between the two color codes is that the orange and green pairs are interchanged. There’s no difference in connectivity between the two standards that a T568B patch cable can work fine on a T568A cabling system, and visa-versa. Usually, T568B wiring standard is regarded as the preferred wiring pattern. Here we use T568B standard. After separating the four pairs, now there’re 8 individual wires. Arrange the Cat5e cable order, making the 8 wires in T568B color sequence.

Figure 4: Wiring standards.

Step Four: Pinch the 8 wires between fingers and cut off the wires to keep them neat and aligned. Note that, the insulation on the Cat5e cable should be just inside the bottom of the Cat5e RJ45 connector. The wires should be cut off so that they can line up evenly with the top of the RJ45 connector.

Step Five: Plug the wires into the RJ45 connector, making sure each wire goes all the way to the top of the RJ45 connector. Otherwise, the newly crimped RJ45 connector may be invalid.

Step Six: Use the crimping tool to crimp the newly produced RJ45 connector and press hard, making sure the contacts of the connector entirely connected with the 8 wires. Then, one end RJ45 connector of Cat5e cable is achieved.

Repeat step one to step six on the other end of the Cat5e patch cable. But note that, when doing Cat5e crimping, there’re two kinds of Ethernet cables can be made, straight through and crossover. For the straight through type, just use the same wiring standards on both ends of the cable. It’s often called “patch cable”, designed for almost all purposes like connecting the computers to routers. For a crossover type, use T568A on one end and T568B on the other end. The purpose of this cable type is to connect one computer to another without using a router, switch or hub.

Figure 5: RJ45 Cat5e cable crimping is completed.

Last Step: Use a cable tester to test the crimped Cat5e cable, guaranteeing it can work fine.

Reliable Ethernet Cable Assembly Source

Crimping RJ45 Cat5e cable is not much difficult. Just prepare the stripping and crimping tools, and follow the above steps, you can make it. However, to successfully complete this job, it’s better to use cables and tools with good quality. At FOCC, you will find the highest quality Ethernet cables and tool assembly for the most critical networks. All the RJ45 Ca5e/Cat6/Cat6a/Cat7/Cat8 cables have fully passed the Fluke Channel Test, delivering excellent performance. They adopt PVC CM jacket design, which provide better fire rating than PVC jacket. Plus, FOCC copper patch cables apply oxygen-free copper for high electrical conductivity and low signal transmission attenuation. FOCC also provides a set of copper assembly like stripping knife tool, punch down tool, and network installation tool kit. These tools are with the highest quality control.

FAQ

1. What is crimping an RJ45 connector?

Crimping is the process of physically attaching an RJ45 modular plug to the end of an Ethernet cable. A crimping tool is used to simultaneously pierce the wire insulation with the connector’s pins and secure the cable to the plug.

2. What is the T568B wiring standard?

T568B is one of two recognized color code standards for terminating an Ethernet cable. The wire order from left to right (pin 1 to 8) is: Orange/White, Orange, Green/White, Blue, Blue/White, Green, Brown/White, Brown. It is the most widely used standard in the United States and for commercial networks.

3. What’s the difference between T568A and T568B?

The only difference is the swapping of the green and orange wire pairs. In T568A, the green pair is on pins 1 & 2 and the orange pair is on pins 3 & 6. In T568B, the orange pair is on pins 1 & 2 and the green pair is on pins 3 & 6.

4. Which wiring standard should I use, T568A or T568B?

For standard patch cables, it doesn’t matter which you use, as long as both ends of the cable are wired to the same standard. However, T568B is far more common in commercial applications. The best practice is to check and match any existing wiring standard already in place.

5. What tools do I need to crimp an Ethernet cable?

The essential tools are a bulk Ethernet cable, RJ45 connectors, an RJ45 crimping tool, and a wire stripper/cutter. A network cable tester is also highly recommended to verify your work.

6. How do I test my crimped RJ45 cable?

Use a network cable tester. Plug one end of the cable into the main tester unit and the other end into the remote unit. Turn it on, and it will automatically check the pin-out. A passing result shows a sequential light pattern (1 through 8) on both units, indicating all connections are correct.

7. What happens if I get the wire order wrong?

If the wire order is wrong, the cable will not function correctly or at all. A cable tester will immediately show a “miswire” or “split pair” fault. The only fix is to cut off the connector and terminate it again with the correct color code.

8. Why is it important to keep the wire twists close to the connector?

The twists in the wire pairs are crucial for canceling out electromagnetic interference (EMI) and crosstalk from adjacent pairs. Untwisting the wires more than 1/2 inch (1.25 cm) from the connector can degrade the cable’s performance and may cause it to fail certification standards.

9. What are pass-through RJ45 connectors?

Pass-through connectors have small holes in the front that allow the individual wires to pass completely through the connector. This makes it easier to verify the correct wire order before crimping and helps ensure a tighter, more reliable connection.

10. Can I crimp an RJ45 connector without a crimping tool?

No. While makeshift methods exist, they are unreliable and likely to damage the connector or create a faulty connection. A dedicated crimping tool is essential as it applies precise, even pressure to all 8 pins simultaneously.

11. How much of the outer cable jacket should I strip off?

You should strip approximately 1 inch (2.5 cm) of the outer jacket. This provides enough length to untwist and arrange the wires, which are then trimmed down to about 1/2 inch before being inserted into the connector.

12. What is a crossover cable?

A crossover cable is a special Ethernet cable wired with the T568A standard on one end and the T568B standard on the other. It was historically used to connect two similar devices directly, like two computers, without a switch. Most modern network devices have Auto MDI-X, which makes crossover cables largely obsolete.

13. Is it cheaper to make my own Ethernet cables?

For standard short lengths (1-10 feet), it is often cheaper and easier to buy pre-made, factory-tested patch cords. Making your own cables becomes cost-effective when you need custom lengths, are running cable through walls for permanent installations, or need to make frequent repairs.

14. What type of RJ45 plug do I need for Cat6 cable?

You must use RJ45 plugs specifically designed for Cat6 cable. Cat6 wires are thicker than Cat5e wires, and Cat6 plugs have staggered pin layouts to accommodate the larger wire gauge and reduce crosstalk between the pairs.

15. What is the most common mistake when crimping RJ45 connectors?

The most common mistake is arranging the wires in the wrong color order before inserting them into the connector. The second most common mistake is not pushing the wires far enough into the connector, resulting in one or more pins not making contact with the wire.