Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
48 Cards in this Set
- Front
- Back
____ bonds the electrical systems grounding electrode system to the PBB (Primary Busbar) |
Telecomm Bonding Conductor (TBC) |
|
Copper conductor that interconnects the PBB to the SBB (Primary Busbar to Secondary Busbar) |
Telecomm Bonding Backbone (TBB) |
|
Recommended as a primary bonding design to accommodate the needs of the site |
Telecomm Bonding Backbone (TBB) |
|
Insulated, stranded copper conductor is used to equalize potentials between SBB's (Secondary Busbar) on the same floor of a structure |
Backbone Bonding Conductor (BBC) |
|
TIA-607-C recommends that a _____ be made on every third floor and the top floor |
Backbone Bonding Conductor (BBC) |
|
______ Connects equipment cabinets and racks to closest PBB or SBB. |
Telecomm Equipment Bonding Conductor (TEBC) |
|
Typical Connections on a busbar are made using _____ |
Bolts or crimps Exothermic Welding |
|
Lugs when possible will have _____ |
2 hole Irreversible Inspection port |
|
______ is a set of conductors or conductive elements formed into a mesh grid |
Supplemental Bonding Network |
|
Integrity of bonding connections cannot always be easily determined because of: |
Distance Access Other parallel bond connections that often exist |
|
Visual inspection of bonding connections can reveal problems such as: |
Loose connections Corrosion Physical damage System modifications |
|
It is essential for the installer to perform metering measurements upon completion of work with bonding and grounding. They should be made for |
2-point bonding resistance True root mean square ac current The dc current The ac outlet wiring polarity/conductor impedance |
|
Recommended max. value for bonding resistance between the meter lead and busbar is _____ |
0.1 ohms (100 milliohms) |
|
The presence of ac current on bonding conductors impacts personal safety and equipment performance, the cause of this unwanted current may be: |
Induction from nearby ac currents Faulty wiring Breakdown of ac circuit conductor insulation Incorrect wiring condition at an ac outlet, subpanel, or other intermediate point in the ac electrical distribution system |
|
Wiring polarity/grounding impedance testers are useful to measure: |
Hot,neutral, and equipment grounding conductor impedance Wiring polarity Possible improper neutral/equipment ground bonds at outlets |
|
Basic function of telecomm circuit protectors: |
Arresting surges or overvoltages that come from exposed circuit pairs Protecting against sustained hazardous currents that may be imposed |
|
3 types of telecomm circuit protectors |
Primary Secondary Data and Fire Alarm |
|
These must be installed as near as possible to the point at which the exposed cables enter the building, and grounding conductors must safely carry lightning and power fault currents |
Primary Protectors |
|
In addition to voltage protection this type must protect against sneak current. |
Secondary protectors |
|
Sneak current can be caused by |
Power faults, which are too low in voltage to operate primary protectors Station equipment that will draw excess current and overheat station wire Induction from power lines |
|
Though not required by codes, these modules must primary protection against lightning transients. They do not have the ability to protect against power faults |
Data and Fire Alarm Protectors |
|
A _____ is required where a circuit is exposed to electrical power faults and lightning |
Primary protector |
|
Interbuilding circuits have a lightning exposure unless any of the following conditions exist |
Interbuilding cable runs of 140 ft or less are directly buried or in underground conduit The area has an average of 5 or fewer thunderstorm days per year (and earth resistivity is less than 0.1 ohms) Circuits are in large metropolitan areas where buildings are close and high enough to intercept lightning |
|
_____ the original protectors. An air gap between 2 elements is set to arc at 300V and 1000V and conducts a surge current to a grounding conductor. Respond slowly at excess of 15 nanoseconds |
Carbon Blocks |
|
_____ are arresters that operate the same as carbon blocks, arcing over a gap to a grounding conductor. Arc at lower voltages providing better protection than a carbon block. Reaction times of 10 to 15 ns |
Gas Tube |
|
_____ arresters rely on high-power semiconductor technology. Reaction times are 3 to 5 ns With clamping voltages of 150V to 300V |
Solid State |
|
Protector terminals should be located up to ______ away from the electrodes |
20ft (6.1m) |
|
Number of pairs for a minimum capacity 12AWG? |
1-2 |
|
Number of pairs for a minimum capacity 10 AWG |
3-6 |
|
Number of pairs for a minimum capacity 6AWG |
> 6 |
|
Aside from the concern for the size of the protector ground conductor, the installer also must consider the variables that may affect the conductors impedance when exposed to ac transient events. What are the variables |
Tightness of connections Length of the conductor Bend radius of the conductor Number of bends in the conductor path |
|
Secondary protectors may include |
Heat Coil Sneak current fuse Positive temperature coefficient resistor |
|
All bonding conductors need to meet this criteria |
Green jacket Shall not decrease in size as bending path moves closer to the termination point on the busbar Bonded with 2 hole lug No bend shall exceed 90° minimum inside bend radius of 8in (10x the diameter is recommended) |
|
Bonding conductors are given specific names to denote function. These are? |
TBC - Telecomm Bonding Conductor TBB- Telecomm bonding backbone BBC - Backbone bonding conductor TEBC- telecomm equipment bonding conductor |
|
A _____ is a conductor used for the joining of metal parts together to firm an electrically conductive path |
Bonding Conductor |
|
Typical binding connections made to an SBB (Secondary Busbar) |
PBB- Primary Busbar Cable tray Ladder rack Equipment racks and cabinets Cable shields Other conduits Supplementary bonding network |
|
For the primary busbar in addition to the connection to the ac electrical grounding system, other connections can be made, what are they? |
Primary and secondary surge protectors Cable tray Equipment racks Ladder racks Branch circuit panels Power conditioning equipment Cable shields Battery rack Other conduits |
|
Primary busbar (PBB) should _____ |
Be located in the EF Be adjacent to telecomm circuit protectors Serve equipment in the same room Have an isolated mount Be located to minimize bonding conductor length |
|
Busbar measurements |
4 inch tall 1/4 inch thick Long as you need 2 inch standoff (Space from wall) |
|
Telecomm bonding and grounding infrastructure is comprised of 4 general catagories |
Busbar Bonding conductor Connector Supplemental bonding network |
|
Bonding and grounding infrastructure includes ________ And may include ________ |
--Includes: Telecomm Bonding Conductor (TBC) Primary Busbar (PBB) --May include: Telecomm Bonding Backbone (TBB) Telecomm Equipment Bonding Conductor (TEBC) Secindary Busbar (SBB) Backbone Bonding Conductor (BBC) |
|
Usually a rod, pipe, or plate in direct contact with the earth for the purpose of providing a low-impedance connection to the earth |
Grounding electrode |
|
Used to connect the grounding electrode to either the equipment grounding conductor, or to the grounded conductor of the circuit at the service equipment. |
Grounding Electrode Conductor (GEC) |
|
The installer must recognize that the following 3 distinct yet interconnected grounding systems should be in place at every site |
Ac grounding electrode system Equipment grounding system Telecomm bonding infrastructure |
|
Bends of the bonding conductors terminating at the PBB or SBB shall have a minimum inside bend radius of: |
8in (200mm) |
|
Equalize voltages between metallic surfaces or equipment within telecomm spaces in the event of Lightning Electrostatic discharge Electromagnetic induction Ac electrical system faults |
Telecomm Bonding Infrastructure |
|
Establishes a zero voltage reference for ac electrical power systems Provides a path for dissipation of currents due to lightning or accidental contact with higher voltage systems Provides a path for the dissipation of electrostatic discharge currents |
Ac grounding electrode system |
|
Zero volts on all equipment enclosures Intentional path for fault currents Voltage reference for power supply |
Equipment grounding system |