C7 Grounding & Bonding for Low Voltage Systems 5

Question 1

Which NEC article specifically covers grounding and bonding requirements for network-powered broadband communications systems?

Accepted Answer

Article 830

Answer

NEC Article 830 addresses network-powered broadband communications systems, including their grounding and bonding requirements.

Question 2

A low voltage contractor is bonding multiple equipment racks in a data room. The bonding conductor between racks should be connected to the:

Accepted Answer

Each rack individually run back to the TMGB using star topology

Answer

TIA-607 recommends a star (home-run) topology where each rack is bonded individually back to the TGB to prevent cascading impedance and ground loops.

Question 3

What is the purpose of an intersystem bonding termination (IBT) device as defined in NEC 250.94?

Accepted Answer

To provide a grounding point for multiple low voltage systems at a common accessible location

Answer

NEC 250.94 requires an IBT to provide an accessible bonding point for communications, CATV, and other low voltage systems at or near the service entrance.

Question 4

A C7 contractor installs a structured cabling system in a multi-story building. Telecommunications grounding busbars (TGBs) on each floor must be bonded back to the TMGB using:

Accepted Answer

A telecommunications bonding backbone (TBB)

Answer

TIA-607 defines the Telecommunications Bonding Backbone (TBB) as the conductor that interconnects TGBs on each floor back to the TMGB.

Question 5

When a coaxial cable for satellite TV enters a building, the outer shield of the cable must be bonded before the cable connects to the first piece of equipment. What is this bonding point called?

Accepted Answer

Antenna discharge unit (ADU)

Answer

NEC 820.100 requires an antenna discharge unit (ADU) at the entry point of coaxial cable to bond the shield and discharge static or lightning energy before it reaches equipment.

(C7) California C7 Low Voltage Systems Contractor Certification Practice Test

(C7) California C7 Low Voltage Systems Contractor Certification Practice Test

C7 Grounding & Bonding for Low Voltage Systems 5