Make a custom Ethernet patch cable by terminating twisted-pair cable with RJ45-style 8P8C plugs. A reliable cable depends on matching the cable and connectors, following one wiring standard at both ends, and testing the finished pin map.

Tools and materials

• Category-rated twisted-pair cable and matching RJ45-style plugs
• Crimping tool designed for the plug type
• Cable stripper or jacket tool
• Ethernet cable tester

Choose T568A or T568B

Both T568A and T568B are recognized wiring schemes. Use the same scheme at both ends for a standard straight-through patch cable, and match the wiring already used in your network. From pin 1 through pin 8, the color order is:

• T568A: white/green, green, white/orange, blue, white/blue, orange, white/brown, brown.
• T568B: white/orange, orange, white/green, blue, white/blue, green, white/brown, brown.

Fluke Networks notes that both schemes are allowed and have the same transmission performance when used consistently. See its T568A vs. T568B wiring guide.

Terminate the cable

1. Measure and cut the cable to the required length.
2. Strip only enough outer jacket to separate and arrange the pairs. Avoid nicking the insulation on the conductors.
3. Untwist each pair only as much as needed, arrange conductors in the selected pin order, and keep the twists close to the plug as its design allows.
4. Trim the conductors evenly, insert them fully in the correct positions, and make sure the cable jacket is captured by the plug’s strain relief.
5. Crimp the plug using the matching tool. Repeat with the same wiring scheme at the other end.

Test before installation

Use a cable tester to verify all eight conductors are continuous and mapped pin-to-pin without opens, shorts, or crossed pairs. If the tester reports a fault, reterminate the cable and retest it before connecting equipment. Label the cable and record the standard used.

For permanent or high-performance network runs, follow the applicable cabling standard and use components rated for the installation. A plug that fits the cable may still be incompatible with its conductor type or category.