Electrical – Using unshielded RJ45 with shielded Cat6 in a server cabinet

cablesethernetrj45

I'm about to do cabling in a server rack that consists of two switches and forty 1U servers. Since every server has three ethernet cables attached we'll have around 120 cables in a single rack.

  1. Is putting unshielded RJ45 connector on a shielded Cat6 ethernet cable a good idea? Since the RJ45 connectors are very close to the endpoints, does it really matter (EMI-wise)?

  2. How important is grounding of that cable? Should I go extra mile and put RJ45 connectors with metal jackets that connect to the external metal shielding of Cat6 cable?

Thank you in advance.

Best Answer

Since you have STP, you should terminate them to gnd for RF improved performance.

Signal Integrity and Group delay times vs f for CAT6 signals are improved with a grounded shield rather than,a floating shield that couples the leakage of all signals to the ground. But this property is depending on cable lengths up 50m or 100m in future drivers.

Avoid cable kinks and shape bend radius smoothly > 4Dia and avoid shield strip > cable dia. at ends.


While shielded components do cost slightly more than UTP, the increased performance and reduced testing time can ultimately lower the total cost of ownership.

The next generation cabling systems that perform beyond 10 Gbs transmission speeds will require shielded cabling and components, which makes STP systems more future proofed than UTP.

The result is similar lifetime costs for both STP and UTP systems.