Cat5e Wiring Diagram

Cat5e Cable Structure and Cat5e Wiring Diagram
Cat5e Cable Structure and Cat5e Wiring Diagram

This CAT5 wiring diagram and crossover cable diagram will show an installer how to properly connect a CAT-5 cable with RJ45 connections for both ordinary network cables and crossover cables. Please keep in mind that these instructions apply to both CAT-6 and other types of 4 twisted pair network cable.

Cat5e Wiring Diagram

A cable can be wired correctly in terms of continuity but not in terms of pairing. This frequently occurs when the cable is terminated in the same way on both ends, but in the incorrect order. To detect this type of problem, you’ll need to run a dynamic or AC test. The cable has correct continuity and will most likely generate crosstalk if the only problem is a split pair error. Crosstalk is the electrical process of induction that causes signals carried by one pair of conductors to leak onto another pair. Because the crosstalk is carried magnetically, the conductors do not need to make touch with each other. This is an undesired consequence that might cause data signals to move slowly or not at all over a long cable section. The wire twists of Cat5e cable are designed to considerably reduce crosstalk and associated side effects.

Electro Magnetic Interference (EMI) is a signal that is induced into the cable that is undesirable. EMI, on the other hand, is usually caused by a source that is external to the cable. This could be a power cable or device, or neighbouring Cat5e cables that do not meet the 568A and 568B specifications. Attenuation is the loss of signal in a cable segment as a result of the wire’s resistance as well as other electrical elements that add to the resistance. Longer cable lengths, shoddy connections, shoddy insulation, high levels of crosstalk, and EMI all add to the overall attenuation. The 568A and 568B standards were created to provide more effective communications in a Cat5e cable segment over longer distances than non-standard systems. Because it transmits data via light rather than electrical current, fibre optic cable is the only media that is totally immune to crosstalk and EMI.


Before you start making conventional Cat5e patch cables, keep in mind that the procedure described here is only one option. It isn’t the most effective way. Before you begin, double-check that you have all of the necessary tools and materials. A length of Cat5e certified cable and many RJ-45 connections are required. For optimal results, we recommend cutting and terminating RJ-45 plugs with a quality ratcheting tool like the renowned IDEAL Telemaster Tool.

Most crimp tools feature two blades: one for entirely cutting through a cable and the other for removing the cable’s outer jacket. Cut the cable to length using the first blade. Then, with the second blade, cut about 1 inch of the cable’s outer jacket, exposing all of the wires inside. When removing the cable’s jacket insulation, be careful not to cut the internal wires.

The Cat5e cable contains eight wires when the jacket is removed. Cut the string and untwist the wires back to within one-eighth inch of the jacket if there is one.

In the sequence in which the wires will be crimped, fan them out from left to right. A standard patch cable is created by using the same colour scheme (568A or 568B) on both ends, as demonstrated in the 568A-568A and 568B-568B drawings below.

With the wires aligned and flattened out, trim the wires equally with the cutting blade, leaving about a half inch exposed.

Carefully enter the wires into the RJ45 connector as indicated below, with the clip facing away from you.

After you’ve placed two RJ45 connectors on both ends, you’ll need to check the quality of all connections to make sure the pinouts are correct. This is a critical phase that is sometimes missed, owing to the high cost of testing equipment. Shorts, openings, miswires, reversals, and split pairs can all be detected with the LanRover Pro TP600. This expert tester will also assist you in determining the final length of the cable you created.

As long as both devices comply with the MDIX standard, two Ethernet switches can be linked with a regular patch connection. All 10/100 RJ45 ports on N-TRON Ethernet switches employ this technology. In essence, the MDIX standard performs crossover operations without the need for user setup. It enables the switch to align the wires properly internally. A cross-over cable can be used to link similar devices, such as legacy hubs or Network Interface Cards (NICs), in specific circumstances. As a result, the cable will perform the crossover function physically. As demonstrated in the 568A-568B diagram below, a crossover cable can be simply made by employing the 568A scheme on one end and the 568B scheme on the other.


Most N-TRON devices do not require the usage of shielded connections between them (please consult the user manuals for specific details). If shielded cables are required, it is usually best to attach the shield solely on one end to avoid ground loops and interference with low-level signals (i.e. thermocouples, RTD, etc.). For use with N-TRON switches, Cat5e cables that meet EIA-568A or 568B requirements are required.

In systems without low-level analogue signals, completely shielded cables terminated to chassis ground at both ends are acceptable if all Cat5e patch cable distances are short (i.e., all Ethernet devices are placed in the same local cabinet and/or referenced to the same earth ground).

Mark Funk
Mark Funk is an experienced information security specialist who works with enterprises to mature and improve their enterprise security programs. Previously, he worked as a security news reporter.