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Appendix C
Measurement Methods and Limits
C-13
Tester Performance Levels
There are two types of performance levels you need to consider when preparing to
perform cable testing:
•
The performance category of the cable system.
•
The accuracy of the field tester.
Twisted Pair Cable Categories
Categories Description
CAT 1 and 2 UTP, not recommended for LAN use.
CAT 3 Four pairs with three twists per foot. Rated for signals up to
16 MHz.
CAT 4 Four pairs per foot. Rated for signals up to 20 MHz.
CAT 5 Four pairs with eight twists per foot. Rated for signals up to
100 MHz.
CAT 5E Same characteristics as CAT 5. Higher quality cable (low
crosstalk). Rated for signals up to 200 MHz.
CAT 6 Four pairs with each pair wrapped in foil insulation. Rated
for signals greater than 250 MHz.