Electrical Inspection
Bonded
Connected to establish electrical continuity and conductivity.
What should inspectors wear while evaluating electrical panels?
Electrician's gloves, non-synthetic clothing, and safety glasses
Conductors between the main service disconnect to the distribution panels(sub panels) are called _____________.
Feeders
The first kind of residential wiring is called __________
Knob and tube
The underground and grounding conductors can share a common bus ________.
Never
Can a ceiling fan be installed on a standard ceiling electrical box?
No. Remember that fixtures under 35 pounds must be mounted to a box rated for fan-support, and fixtures over 35 pounds cannot be supported by the electrical box at all
Ampacity
The maximum current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its maximum temperature rating.
T/F: All conductors should be protected within 6 feet of the scuttle opening. This means that no cables should be run on top of joists in this area. If they run perpendicular to the joist, they should either be drilled through the timbers and have a running board over the top, or be stapled to the side of a running board.
True
T/F: InterNACHI does NOT require and does NOT recommend home inspectors to remove the dead front (panel cover)
True
T/F: Panels should be on a free wall space not less than 30 inches wide, have a clear 36 inches of space in front of them, and have 6 feet and 6 inches of head room. The panel, though, is not required to be centered in this space.
True
T/F: Romex cable cannot be exposed to ultraviolet light (sunlight)
True
T/F: all receptacles in garages and unfinished basements must be GFCI-protected, including sump pumps.
True
T/F: the home inspector should pay special attention to blue-button Square D breakers, and advise the client that they may be subject to recall
True
The available service amperage is based on the _________-rated component
lowest
Properly bonding all ____________ within an electrical system helps ensure a low-impedance fault current path.
metal parts
100 amps is the ____________ service required for a new single-family home.
minimum
Electric water heaters should be fed with 10 awg ___________ copper conductors
minimum
The ___________ copper wiring size carrying 120 volts should be 14 awg
minimum
Electrical panels do not have to be fully enclosed as long as no hole is bigger than _________
none of these
what should an inspector recommend if tree branches are near the service supply wires?
recommend that any limbs within 5 to 6 feet of the cable assembly be cut back.
A bonding connection __________ connect the ground bus to the electrical enclosure
should
The electrical supply ____________ able to be shut down with 6 or fewer moves of the hand.
should be
Several grounded conductors _________ terminate on the same lug.
should not
How often does Romex need to be secured?
stapled within 12 inches of metal enclosures (and 8 inches from plastic gang boxes), and every 4 feet and 6 inches of run length.
How often do AC cables need to be secured?
stapled within 12 inches of metal enclosures, and every 4 feet and 6 inches of run length. MC cable has a run-length that is extended to 6 feet between the required supports.
Wiring within 1-1/4 inches to the front of a ________ requires protection
stud
Water dripping from an electrical panel should be _________________
tagged as an immediate hazard and deferred to an electrician
Power
the amount of work that the electrical flow can do. This is expressed as watts or kilowatts (1,000 watts).
Service Drop
the overhead service conductors located between the utility electric supply system and the service point.
Service Point
the point of connection between the facilities of the service utility and the wiring at the house.
A 4 wire 240V cable assembly has _____ , one neutral, and one ground conductor
two hots
Which of the following should be reported as a problem with an electrical panel? -pigtails (two wires joined to a common breaker) -unlinked double-pole breakers -splices in the panel -GFCI breakers
unlinked double-pole breakers
_____________ cable assemblies should not be in crawlspaces
unsupported
Electromotive Force
what drives electrons along the conductor, and is expressed as voltage or volts.
Which of the following would not be an electrical panel defect? -missing knockouts -rusted enclosure -wire splices -lack of legend
wire splices
A service entrance with ______ connected conductor(s) is a 3-phase supply.
4
What is the minimum circuit for stoves?
40 amp
A service drop should be at least ________ away from any nearby trees.
5 to 6 feet
The minimum size for a copper grounding electrode rod is ___________.
5/8-inch diameter and 8 feet long
Branch Circuit
A branch circuit are the conductors between the final overcurrent device protecting the circuit and the outlet(s)
Current
A measurement of the rate of flow of electricity through a conductor. Current is measured in amps.
AFCIs are required to protect __________ receptacles, if properly wired
bedroom
A staircase with six or more risers requires a light switch at _______________________ of the staircase
both the top and bottom
The grounded and grounding conductors ______________ bus in the service panel.
can share a common
How often does metal conduit/EMT need to be secured?
clamped within 36 inches of enclosures, and every 10 feet of run length.
A _______________ cause of arc flashes when removing panel fronts is incorrect fasteners
common
GFCI receptacles can protect _________ circuits
downstream
GFCIs are designed to sense any difference in current between the supply on the ungrounded (hot) conductor in a circuit and the __________
grounded (neutral) conductor
Gas supply piping cannot be used as a ______________.
grounding means
The inspector should not report all ___________ electrical splices as improper
in-panel
A split-bus electrical panel uses a double-pole breaker to ___________ the 120-volt circuits.
isolates
Which of the following locations required fixed lighting? -bedrooms -all crawlspaces -kitchens -bathrooms
kitchens
Resistance
limits the conductor's ability to allow the flow of electrons, just as friction causes losses in any pipe or duct work. This is expressed in Ohms.
An Inspector should report any knob and tube wiring as in need of further evaluation by an electrical contractor due to the following reasons:
1. The insulation is often very brittle and leaves conductors exposed when disturbed. 2.All circuits are ungrounded, which will not suit many modern electronics, such as computers, televisions and stereos. 3. The conductors are often buried in attic and wall insulation. This is a problem, as they were designed to work in free air. 4. The wire gauge is commonly 14-awg only, which is not sufficient for most modern household needs. 5. It's very common for knob-and-tube wiring to have been added to over the years, and it may contain many splices outside of approved enclosures. (Originally, joints in knob-and-tube were all spliced, soldered and taped outside of enclosures.)
Inspectors should follow these basic safety rules when inspecting live electrical components:
1. Wear protective eye-wear. 2. Wear gloves. 3. Do NOT wear nylon or polyester clothing. 4. Do NOT allow the client to get between the inspector and any live components. 5. Visually inspect the panel or box without removing the dead front or cover. 6. Do NOT touch a panel or box that is either very rusted or shows signs of moisture. 7. Do NOT touch any panel or box that is buzzing or arcing. 8. Frequently test for stray voltage using a non-contact AC voltage tester. 9. Do NOT insert any probes or tools into electrical panels or boxes. 10. NEVER carry or position a ladder near an electrical line or cable.
An arc flash can have various catalysts:
1. excess dust 2. condensation 3. corrosion 4. component failure 5. faulty system installation 6. dropping a metal tool, which may cause even a small spark 7. accidental contact.
Inspectors are not required to:
1. measure or determine the amperage or voltage of the main service equipment 2. remove panelboard cabinet covers or dead fronts 3. insert any tool, probe or device into the main panelboard, sub-panels, distribution panelboards, or electrical fixtures 4. operate any electrical disconnect or over-current protection devices.
Warning signs that a panel may need further evaluation:
1. scorch marks on the dead front or the panelboard door, indicating a past or recent arc flash 2. rust, which indicates past or recent moisture intrusion 3. missing or open breakers that cannot be confirmed to be de-energized 4. overloading of the circuits with DIY wiring 5. uninsulated wiring 6. excessive dust, dirt and debris inside the panelboard 7. any signs of water inside, around or below the panelboard, which can lead to shock or electrocution
Knob and tube wiring was common in the US prior to ______
1930
Most homes constructed between 1930 and ______ originally had 60-amp service.
1950
Service drops around a swimming pool should be _______
22-1/2 feet above and 10 feet horizontally away
The clearance for open overhead service conductors from the front, bottom, and sides of windows that open is ______ feet.
3
Service drops should never pass closer than ______ above the ridge of a conventional pitched roof.
3 feet
How many amps are electric clothes dyers?
30 amp
Electrical service panels should be in a clear space measuring ____________
30" wide by 78" high by 36" deep
_________________ need to be bonded to ground.
All panel enclosures
AWG
American wire gauge (AWG) is a standardized wire gauge system used since 1857 predominantly in North America for the diameters of round, solid, nonferrous, electrically conducting wire. The cross-sectional area of each gauge is an important factor for determining its current-carrying capacity. Increasing gauge numbers denote decreasing wire diameters.
AFCI
Arc-Fault Circuit Interrupter (AFCI) is a device that provides protection from the effects of arc-faults by recognizing arcing and deenergizing the circuit when an arc-fault is detected (tripping the circuit)
Romex
Romex is a trade name for a type of NM cable. Romex is the most commonly used wiring in homes. The proper name for this cable is nonmetallic sheathed cable. A 14/2 with ground would contain three 14-gauge conductors: one black insulated conductor (the hot); one white insulated conductor (the neutral); and one bare conductor (the ground wire).
Most areas require two means of _________ grounding.
Separate
An electrical service mast that extends 5 feet or more above the roof surface needs to be supported ________.
Separately
An underground service entrance is called a ________.
Service Lateral
Which of the following would the inspector require a specialist? -stranded aluminum wiring -copper clad wiring -solid conductor aluminum branch wiring
Solid conductor aluminum branch wiring
Common Ohms Laws
Watts equals Volts times Amps (W=ExI) Amps equals Watts divided by Volts (I=W/E)