DCI Cabling Standards 5 — Questions and Answers
Question 1: What is the minimum bend radius for a Category 6 UTP horizontal cable during installation (not under tension)?
- 4 times the cable diameter
- 8 times the cable diameter (Correct answer)
- 10 times the cable diameter
- 15 times the cable diameter
Correct answer: 8 times the cable diameter
TIA-568-C.2 requires a minimum bend radius of 4 times the cable diameter under tension and 8 times at rest for Cat 6 UTP.
Question 2: Which standard provides guidance on installing structured cabling in industrial environments subject to harsh conditions?
- TIA-568-C.1
- TIA-1005-A (Correct answer)
- TIA-942-B
- TIA-862
Correct answer: TIA-1005-A
ANSI/TIA-1005-A is the Telecommunications Infrastructure Standard for Industrial Premises, addressing harsh electrical and environmental conditions.
Question 3: How does TIA-568 define the 'permanent link' in a copper cabling system?
- The cable from the IDC to the work area outlet only
- The channel excluding equipment cords at both ends (Correct answer)
- The full end-to-end path from switch to device
- The backbone cable between MDF and IDF
Correct answer: The channel excluding equipment cords at both ends
The permanent link includes the installed horizontal cable and connecting hardware but excludes the patch/equipment cords at each end.
Question 4: What is the maximum pulling tension allowed for 4-pair UTP horizontal cable during installation per TIA-568?
- 11 lbs (5 kg)
- 25 lbs (11 kg) (Correct answer)
- 50 lbs (23 kg)
- 75 lbs (34 kg)
Correct answer: 25 lbs (11 kg)
TIA-568 limits pulling tension for 4-pair UTP horizontal cable to 25 lbs (110 N) to prevent damage to the cable geometry and electrical performance.
Question 5: Which performance parameter measures the difference in signal propagation delay between the fastest and slowest pairs in a UTP cable?
- Insertion loss
- Near-end crosstalk (NEXT)
- Propagation delay skew (Correct answer)
- Return loss
Correct answer: Propagation delay skew
Propagation delay skew measures the timing difference between the fastest and slowest pairs, critical for applications using all four pairs simultaneously.
Question 6: Under TIA-568, what is the maximum number of consolidation points (CPs) permitted in a single horizontal cable run?
- None — CPs are not recognized
- One (Correct answer)
- Two
- Three
Correct answer: One
TIA-568 recognizes a maximum of one consolidation point per horizontal cable run, used in open-office furniture cabling scenarios.
Question 7: Which IEEE standard defines the 10GBASE-T specification that drove the development of Category 6A cabling?
- IEEE 802.3an (Correct answer)
- IEEE 802.3ab
- IEEE 802.3z
- IEEE 802.3ae
Correct answer: IEEE 802.3an
IEEE 802.3an defines 10GBASE-T, the 10-Gigabit Ethernet over twisted-pair copper standard that requires Category 6A or better cabling.
DCI Cabling Standards 5
What is the minimum bend radius for a Category 6 UTP horizontal cable during installation (not under tension)?