Grounding and Bonding, CH 5
The grounding electrode conductor connection must be made at an accessible point located anywhere from the side of the service drop or lateral up to the service equipment enclosure. Which of the following locations are not acceptable for this grounding electrode conductor connection?
Directly buried in the Earth
If the total circular mil area of the largest ungrounded service-entrance conductor for a service is 2000-kcmil copper, what is the minimum size required for a wire-type main bonding jumper for the service?
Don't Have the Answer
When a main bonding jumper is a wire, it must be sized using ? ; alternatively, 12.5% is used when the size of the largest ungrounded service-entrance conductor exceeds 1100-kcmil copper or 1750-kcmil aluminum or copper-clad aluminum.
Table 250.102(C)(1)
The grounding electrode conductor for ungrounded services and grounded services is generally required to be sized based on the size of the largest ungrounded service-en trance conductor using?
Table 250.66
What is the minimum size required for the grounded conductor of a 3-phase, 3-wire, corner-grounded delta system that supplies grounded service?
The grounded conductor must have an ampacity not less than the ungrounded conductors supplied by the system.
A main bonding jumper in listed service equipment can be used without calculation of size because it is provided by the manufacturer and the equipment is listed and identified as suitable for use as service equipment.
True
An important requirement for service equipment is that provisions for disconnecting the grounded conductor (usually a neutral) are provided within the service equipment enclosure.
True
If equipment is identified as suitable for use only as service equipment, it typically includes a terminal or bus for the grounded conductor that is fastened directly to the enclosure; there typically is no main bonding jumper.
True
In addition to the grounding connection at the service, one additional grounding con nection from the grounded system conductor to a grounding electrode must also be made at the transformer or at another point outside the building.
True
The first point of grounding for a building or structure supplied by a utility service is usually within the service equipment enclosure(s).
True
The grounded conductor at the service. carries normal line-to-neutral load current and functions as an intentionally construct ed, low-impedance, effective ground-fault current path, as required in 250.4(A)(5).
True
Grounded service conductors in sizes 4 AWG and larger are required to be identified using which of the following methods?
Any of the Above
The main bonding jumper must be copper, copper-clad aluminum, or another corrosion resistant material and can be in which of the following forms?
Any of the Above
Parallel service conductors are generally not permitted in sizes smaller than ?.
1/0 AWG Copper
If the largest ungrounded service-entrance conductor for a service is 750-kcmil copper, what is the minimum size required for a wire type main bonding jumper for the service?
2/0 AWG Copper
If the largest ungrounded derived phase conductor for an ac generator is 750-kcmil copper, what is the minimum size required for a wire-type system bonding jumper?
2/0 AWG copper
A metal component such as a metal elbow in a run of nonmetallic service raceway is required to be grounded if it is buried not less than 18 inches below grade.
False
The equipment installed on the load side of the service disconnecting means enclosure, such as switchboards and panelboards, have to be identified as either suitable for use as service equipment or suitable for use only as service equipment.
False
Premises wiring systems generally are required to be supplied by a system that is ? and includes a grounded conductor.
Grounded
When a service is supplied by a grounded system (source), the? is required to be routed from the utility supply system or source to the service disconnecting means enclosure and bonded to the service disconnecting means enclosure.
Grounded Conductor
The NEC requires the grounded conductor to be routed with the ungrounded service con ductors to the service disconnecting means enclosure, and bonded to that enclosure. For equipment that is identified as suitable for use as service equipment, this is typically accomplished using a(n)?
Main Bonding Jumper
The connection between the grounded conductor and the equipment grounding conductor or the supply side bonding jumper (or both) at the service best defines which of the following components of the grounding and bonding system?
Main Bonding Jumper
The ? is the common point on a wye-connection in a polyphase system or midpoint on a single-phase, 3-wire system; the midpoint of a single-phase portion of a 3-phase delta system; or a midpoint of a 3-wire, direct-cur rent system.
Neutral Point
The minimum size grounded conductor for a service supplied by a grounded system shall not be smaller than the values in which of the following tables?
Table 250.102(C)(1)