ScTP includes a foil shield and a drain wire that must be grounded. What must be grounded?

ScTP includes a foil shield and a drain wire that must be grounded. What must be grounded?

• A. Drain wire
• B. Outer jacket
• C. Shield braid
• D. Ground strap

Answer: (A)

Shielded cables rely on a grounded shield to divert interference away from the conductors. In ScTP, a foil shield surrounds the pair and a drain wire runs along or attached to that shield. The drain wire is the conductor you terminate to equipment ground or chassis ground, which bonds the shield to ground and keeps it at earth potential. Grounding the drain wire provides the necessary return path for EMI by effectively grounding the shield itself. The outer jacket isn’t a grounding path, and a ground strap isn’t part of the cable assembly. So the component that must be grounded is the drain wire.

Shielded cables rely on a grounded shield to divert interference away from the conductors. In ScTP, a foil shield surrounds the pair and a drain wire runs along or attached to that shield. The drain wire is the conductor you terminate to equipment ground or chassis ground, which bonds the shield to ground and keeps it at earth potential. Grounding the drain wire provides the necessary return path for EMI by effectively grounding the shield itself. The outer jacket isn’t a grounding path, and a ground strap isn’t part of the cable assembly. So the component that must be grounded is the drain wire.