KLOTZ AIS cable guide

STP

An old, but still-used designation for a twisted-pair cable with braided shield. However, the designation does not specify whether the shield type refers to individual pairs or the cable as a whole.

New and more precise designations are set forth in the ISO/IEC 11801 (2002) E standard and take the form of XX/YZZ, as follows:

XX indicates the overall shield

  • U = unshielded
  • F = foil shielding (coated plastic foil)
  • S = braided shielding (braided wire)
  • SF = braided and foil shielding

Y indicates the shielding of the individual pairs

  • U = unshielded
  • F = foil shielding (coated plastic foil)
  • S = braided shielding (braided wire)

ZZ is the twisting type

  • TP = twisted pair (usually)
  • QP = quad pair

Example: An S/FTP is a Screened Foiled Twisted Pair (braided shield for the cable and foil shield for the twisted pairs).