Special Equipment

Chapter 12: Special Equipment

Learning Objectives

Upon completing this chapter, you will be able to:

1.1 Introduction to Chapter 6 and 7

Article 100 defines special equipment as equipment that, due to its design, function, or application, requires rules that modify or supplement the general requirements of Chapters 1 through 4. These rules are found in NEC Chapter 6 (Special Equipment) and Chapter 7 (Special Conditions) . For the Texas Journeyman exam, you must know when a special article overrides a general rule versus when it adds to it.

The general rule of code hierarchy: Chapter 5 (Special Occupancies) applies to locations; Chapter 6 applies to equipment; Chapter 7 applies to conditions that require alternate systems. When a conflict exists between a general rule (Chapters 1–4) and a special rule (Chapters 5–7), the special rule prevails.

1.2 Electric Vehicle Supply Equipment (EVSE) – Article 625

Scope: Article 625 covers conductors and equipment connecting an electric vehicle (EV) to a supply of electricity, including the vehicle itself as a load.

Key definitions:

Disconnecting Means (625.43):

Wiring Methods (625.40):

Ground-Fault Protection (625.50):

Rapid Shutdown (625.54): For PV systems that charge EVs, the EVSE must be listed for rapid shutdown.

Exam Trap: Many candidates confuse the 50 ft "within sight" rule for the EVSE disconnect with the 15 m (50 ft) rule for a service disconnect. They are the same distance, but the EVSE rule is specific to the equipment being supplied. Also, note that the disconnect must be lockable, not necessarily locked.

Field Point: On a job site, always verify the EVSE is listed and that the branch circuit is sized at 125% of the continuous load. For a 32 A continuous EV charger, the branch circuit must be rated at 40 A (32 × 1.25).

1.3 Elevators, Escalators, and Moving Walks – Article 620

Scope: Article 620 covers the electrical equipment and wiring for elevators, dumbwaiters, escalators, moving walks, and similar equipment.

Wiring Methods (620.21):

Disconnecting Means (620.51):

Overcurrent Protection (620.61):

Lighting and Receptacles (620.22):

Exam Trap: The most common trap is the "no other wiring" rule. You cannot run a general-purpose branch circuit through an elevator machine room to supply a nearby office. The room is dedicated to the elevator equipment.

Field Point: When working in an elevator pit, always verify the pit lighting is on a separate circuit with a GFCI, and that the stop switch is within reach. The pit stop switch must be a red, mushroom-type device.

1.4 Industrial Machinery – Article 670

Scope: Article 670 covers the electrical wiring and equipment for industrial machinery, defined as a machine that processes material by cutting, forming, or assembling.

Supply Conductors (670.4):

Disconnecting Means (670.5):

Overcurrent Protection (670.4):

Exam Trap: Do not apply the motor rules of Article 430 to the entire machine. The machine is treated as a single load based on its nameplate. If the nameplate says 60 A, you install a 60 A circuit, even if the sum of the motors inside is 80 A.

Field Point: When installing a new machine, always check the nameplate for the "Maximum Overcurrent Protection" rating. This is the maximum size of the branch circuit fuse or breaker, not the minimum.

1.5 X-Ray Equipment – Article 517 (Part V) and Article 660

Note: X-ray equipment is covered in two places. Medical X-ray equipment is in Article 517, Part V. Non-medical (industrial) X-ray is in Article 660.

Disconnecting Means (660.6):

Wiring Methods (660.4):

Grounding (660.5):

Exam Trap: The 100% sizing rule for X-ray equipment is a common exception to the general 125% continuous load rule. However, if the X-ray unit is used for more than 3 hours at a time (rare), it is considered continuous.

Field Point: In a hospital, X-ray rooms often have dedicated transformers to isolate the high-voltage circuits. Always verify the grounding electrode conductor is sized per Table 250.66, not the branch circuit.

1.6 Information Technology Equipment (ITE) – Article 645

Scope: Article 645 covers equipment and wiring in an information technology equipment room, defined as a room with a raised floor and a dedicated HVAC system.

Key Requirements:

Grounding (645.15):

Exam Trap: Article 645 only applies if the room meets all the conditions: dedicated HVAC, raised floor, and fire alarm disconnect. If any condition is missing, the room falls back to the general rules of Chapters 1–4 (e.g., standard receptacle spacing).

Field Point: When running power under a raised floor, you must use a wiring method that is permitted for the environment. If the floor is used as an air plenum, you must use Type MC cable with a smooth sheath or conduit, not standard NM cable.

1.7 Over 1,000 Volts – Article 490

Scope: Article 490 covers equipment operating at more than 1,000 volts, such as medium-voltage switchgear and transformers.

Wiring Methods (490.30):

Disconnecting Means (490.21):

Grounding (490.24):

Exam Trap: The 2 AWG minimum grounding electrode conductor for high-voltage systems is a common trick. Do not use the 8 AWG minimum from Chapter 2.

Field Point: Working on medium-voltage equipment requires special training and PPE. Always verify the disconnect is open and tagged before approaching the equipment. Use a voltage detector rated for the system voltage.

1.8 Integrated Electrical Systems – Article 685

Scope: Article 685 covers integrated electrical systems, which are units of interconnected equipment that function as a single machine or process (e.g., a printing press line).

Key Rules:

Exam Trap: This article is rarely tested but is a favorite for "which article applies" questions. If the question describes a single machine with multiple motors and a control panel, it is likely Article 670 (Industrial Machinery), not Article 685.

1.9 Code Navigation: Where to Find It

1.10 Practical Field Points and Common Exam Traps

Field Point – Disconnects: For almost all special equipment, the disconnect must be within sight of the equipment. If it is not within sight, it must be capable of being locked in the open position. This is a universal rule that appears in Articles 430, 620, 625, and 660.

Field Point – Nameplates: Always read the equipment nameplate. It is the single source of truth for ampacity, overcurrent protection, and voltage. Never assume the load based on the sum of components.

Field Point – Lockable vs. Locked: A disconnect that is "capable of being locked" means it has a hasp or a provision for a padlock. It does not have to be locked during normal operation.

Exam Trap – Continuous Loads: Most special equipment is not considered a continuous load unless it operates for 3 hours or more. X-ray equipment is a notable exception (100% sizing), while EVSE is always considered continuous (125% sizing).

Exam Trap – Wiring Methods: Special equipment often requires specific wiring methods. For example, elevators require metal conduit, while ITE rooms allow flexible cables under raised floors. Read the question carefully to see if it specifies a room type.

Exam Trap – Article Hierarchy: If a question involves a hospital X-ray machine, you must use Article 517, not Article 660. The medical location rules always take precedence over the general equipment rules.

1.11 Summary

This chapter covers the most heavily tested special equipment articles on the Texas Journeyman exam. Remember the three-step process for any special equipment question:

The NEC is a reference book, not a memory test. Your job is to know where to look and what to look for. Use the Code Navigation table above as your quick reference during the exam. When in doubt, look for the word "shall" – it indicates a mandatory requirement. Good luck.