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Article 310 provides general requirements for conductors rated up to and including 2000 volts.

Insulated conductor types XHHN, XHWN, and XHWN-2 were added to 310.10.

New Table 310.12.

This raceway is several inches above the rooftop therefore no temperature adder is required.

Ampacity Table 310.16 (formerly Table 310.15(B)(16).

Medium Voltage cable is now covered in NEC Article 311.

Conductors at terminals or conductors entering or leaving cabinets, cutout boxes, and meter socket enclosures shall comply with 312.6(A) through (C).

These current sensors were installed to monitor the performance of this panelboard. The panelboard contained 480-volt inverter output circuits from 12 different PV inverters.

It is important to remember that equipment grounding conductors that do not leave the box (such as pigtails) are not counted.

Where the raceway enclosing nonmetallic sheathed cable is complete between boxes, the cable shall not be required to be additionally secured.

A listed outlet box suitable for the sole support of ceiling-suspended (paddle) fan is one option permitted in NEC 314.27(C).

These two boxes were installed facing the dead space behind the wall. After sheetrock is installed, they will not be accessible unless the building finish is removed. Oops.

Both AC and MC cable are considered supported where passing through studs spaced no more than 4 &frac12; foot for AC cable, and 6 foot for MC cable.

This exterior wall will be insulated. Sometimes even an interior wall will be insulated after rough inspection to comply with sound transmission requirements.

A hazardous location rated MC cable.

A coil of cable at a box is not required by code but it might make things easier on future repair work.

NM-PCS cable incorporates Power, Control and Signal circuits.

Type P cable has been used for more than 40 years in harsh environments for offshore drilling operations where oil and mud are common.

Service-Entrance cable examples.

Is the RMC conduit to the temporary construction trailer subject to &ldquo;physical damage&rdquo; or &ldquo;severe physical damage&rdquo;?

Conductors inside LFMC are not permitted to operate higher than the temperature rating of the LFMC. Is this LFMC properly fastened in accordance with 350.30(A)?

Correction factors for the number of current carrying conductors must be applied only to the conductors in cross section B.

It is quite common to see cable trays used to carry DC PV source circuits operating over 600 volts. These cable trays require the DANGER marking.

Cable ties marked Type 2S and 21S have been evaluated for the support of cables.

An expansion splice plate may have slotted holes to allow for movement in the cable tray. A bonding jumper is required where cable tray systems are mechanically discontinuous.

Cables entering equipment from bushed conduit and flanged connections.

Sections 404.9 and 404.10 now apply to control switches.

Many manufacturers have been selling listed switches for years.

Electronic control switches shall be marked by their manufacturer with their current and voltage ratings and used for loads that do not exceed their ampere rating at the voltage applied.

Some electronic control switches are designed for other purposes besides only lighting.

Automatically controlled receptacles shall be replaced with equivalently controlled receptacles.

Receptacles are permitted below a sink, but not face-up.

Receptacles shall be installed no closer 3 feet horizontally from, and 8 feet vertically from the top of the bathtub rim or shower stall threshold.

There are many different types of tamper-resistant receptacles currently available.

According to 406.14(D), the use of single-pole separable connectors shall be performed by a qualified person.

The identification shall be included in a circuit directory that is located on the face, inside of, or in an approved location adjacent to the panel door.

Notice the available fault current marking on the service panel.

This mistake was caught at the final inspection. The electrician went to great expense to provide proper work space for the rear terminals before the job was finally approved.

Panelboards are not permitted face-up.

A properly installed luminaire retrofit kit is not considered reconditioning.

What type of luminaire is permitted in this zone?

In the years to come, ballasts and drivers will have integral lead wires that do not use a grey wire for dimming or control features.

410.116(C) permits luminaires to be installed in or used with a luminaire enclosure that is listed for use in a fire resistance&ndash;rated construction.

If the box can only be accessed by removing the luminaire below it, then it&rsquo;s a code violation.

Horticultural lighting is becoming a popular topic with the cannabis industry.

Lighting equipment identified for horticultural use shall not be installed as lighting for general illumination unless such use is indicated in the manufacturer&rsquo;s instructions.

Section 422.5 requires Class A GFCI protection for many types of appliances.

This is a code violation in the 2020 NEC without a bushing or grommet where the dishwasher cord passes through the cabinet.

Microwave/range hood combination units are permitted to be cord-and-plug-connected.

Stationary generators 600 volts and less shall be listed.

A summary of the code language in NEC 445.18(A), 445.18(B), 445.18(C), and 445.18(D).

Transformers require ventilation to properly dispose of heat.

Plaques or directories shall be installed in accordance with 705.10 and 712.10.

511.8 now applies to underground wiring below Class I locations.

The emergency disconnect switch required by NEC 514.11(A) must be at least 20 feet away but no more than 100 feet. The emergency disconnect shall not disconnect equipment grounding conductors.

Part II of Article 517 does not apply to Optometry.

Tamper-resistant receptacles are not required in an infant nursery of a health care facility.

Battery systems shall be permitted to serve as the alternate source for all or part of an essential electrical system.

When tornados, hurricanes, or other catastrophic disasters occur, a local hospital can quickly become the epicenter of care for the injured and can also become a community gathering point.

Illumination is required for all working spaces about fixed service equipment, switchboards, switchgear, panelboards, or motor control centers installed outdoors that serve assembly occupancies.

A construction office is a relocatable structure, not a mobile home.

The requirements for floating buildings are now located in Article 555.

Transformers and enclosures shall be identified for wet locations. The bottom of transformer enclosures shall not be located below the electrical datum plane. Is this installation code compliant?

Several items need to align to use the new exception in 590.4(G) and go without a cover plate.

This temporary construction power will be subjected to harsh conditions before the job is over, then it will be moved to the next job site.

With the help of a little gravity, the listing labels on this sign should be visible pretty soon after this sign hits the ground.

First responders need to be able to easily find the sign disconnect.

Do you think these two sign retrofitters are following the installation instructions?

Equipment enclosures containing selectively coordinated overcurrent devices shall be legibly marked in the field to indicate that the overcurrent devices are selectively coordinated.

Some manufacturers have EV chargers that can be adjusted to a lower setting to accommodate limited remaining load capabilities of an electric service.

An interactive system may incorporate a power export function allowing the EV to supply power to external loads on the premises.

A splash pad is a fountain with a pool depth of 1 inch or less, intended for recreational use by pedestrians.

Aging swimming pool equipment can create a safety hazard if not properly maintained.

Where a pool pump motor in 680.21(C) is replaced for maintenance or repair, the replacement pump motor shall be provided with ground-fault circuit-interrupter protection.

At least one GFCI-protected 125-volt, 15- or 20- ampere receptacle on a general-purpose circuit shall be located within a pool equipment room.

Revised code language now allows a copper grid for equipotential bonding of perimeter surfaces adjacent to a pool.

The maximum voltage of PV system dc circuits shall be the highest voltage between any two conductors of a circuit or any conductor and ground.

Electronic devices such as diodes are now permitted to satisfy the requirements in 690.9(B).

This UL Listed PV wire complies with the change in 690.31(C)(1). Be sure to use it within the array or plan on putting it in a raceway where it leaves the array.

700.12(I)(2)(3)(b) was used for this example.

LED emergency light above an exit door. Is it compliant with 700.16(B)?

Not enough room in the panelboard to add another breaker might create the need for tapping the feeder directly.

For this feeder option, an overcurrent protective device (OCPD)on the load side of the power source connection shall not be rated greater than the ampacity of the feeder.

For option 1, the sum of 125% of the inverter output circuit current and the rating of the overcurrent device protecting the busbar shall not exceed the ampacity of the busbar.

Paint, plaster, cleaners, abrasives, corrosive residues, or other contaminants can result in an undetermined alteration of Class 1, Class 2, Class 3, and PLTC cable properties.

Cables identified for future use with a tag are not considered abandoned cables.