Texas Master Electrician Course Notes

Start with terminology, system relationships, and the four core calculation patterns. Know the difference between service conductors, feeders, and branch circuits; distinguish grounded (neutral) conductors from equipment grounding conductors; and resolve plan conflicts before sizing anything. The calculations portion expects quick recognition of Ohm’s law, single-phase power, three-phase power, and power factor.

• Calling every white conductor an equipment grounding conductor.

• Write the unknown first, then select the formula that isolates it.

Services are a major scoring area, especially on the calculations portion. Master disconnect location and grouping, service equipment ratings, service grounding/bonding, grounding electrodes, conductor ampacity and terminations, separately derived systems, transformer current, dwelling load calculations, and fault-current/SCCR checks. The 2026 NEC also changes some dwelling service rules and relocates load calculations to Article 120.

• Treating 0.83 as a generic multiplier for every dwelling calculation.

• Services are high weight: know Articles 120, 230, 250, 310, and 450 navigation cold.

Feeder questions test conductor function, ampacity, overcurrent protection, taps, grounding, voltage drop, outside-building disconnects, conductor count adjustment, and load calculations. The key is to keep three separate checks in order: calculated load, conductor ampacity after correction/adjustment, and overcurrent/device ratings.

• Confusing feeder conductors with branch-circuit conductors.

• On any feeder question, write LOAD → AMPACITY → OCPD → VOLTAGE DROP → GROUNDING.

Branch-circuit questions are another heavy-weight area. Know continuous-load sizing, small-conductor OCPD limits, required dwelling circuits, GFCI/AFCI, multiwire branch circuits, receptacle ratings and loads, fixed equipment, terminal temperature, grounding, identification, and voltage drop. The Texas HVAC GFCI modification is narrow and frequently testable.

• Applying 125% to a noncontinuous load.

• For dwelling questions, first identify location: bathroom, kitchen, laundry, bedroom/other AFCI area, garage/outdoor/etc.

This domain is table-and-installation-rule heavy: wet locations, conductor/raceway suitability, conduit fill, physical protection, cable/raceway support, box fill, covers, flexible cords, raceway bends, and ampacity adjustment. Learn the numbers that let you eliminate distractors quickly.

• Calling THHN-only marking sufficient for a wet location without verifying wet-location listing.

• Memorize 53/31/40 and 3 ft/10 ft EMT, 12 in/4.5 ft NM.

Equipment questions reward precise use of listings, ratings, working space, environmental suitability, directories, receptacle replacement rules, appliance disconnects, transformer ventilation, capacitors, grounding, and panelboard compatibility. Always distinguish normal operating rating, interrupting rating, and SCCR.

• Treating breaker ampere rating as its interrupting rating.

• When a question mentions a label or instruction manual, 110.3(B) should be your first thought.

Motors and generators are the heaviest calculation family after services. The exam repeatedly separates table full-load current, nameplate current, conductor ampacity, overload protection, branch-circuit short-circuit/ground-fault protection, controllers, disconnects, multi-motor feeders, and generator neutral arrangements.

• Using nameplate current for every motor calculation.

• Write MOTOR TABLE FLC or NAMEPLATE at the top before calculating.

Control and disconnect questions are low in count but easy points if you separate control functions from true isolation. Verify switch ratings, required disconnects, accessibility, identification, lockable-open provisions, and any equipment-specific rules.

• Calling a stop button or opened control circuit a power disconnect.

• Ask two questions: does it CONTROL the load, or does it DISCONNECT the supply conductors?

Special-occupancy questions are recognition-heavy: hazardous locations, health care, temporary wiring, pools, emergency/standby systems, EVSE, signs, elevators, and agricultural buildings. Start by identifying the occupancy/equipment article, then apply its special rules before general rules.

• Thinking any metal enclosure is acceptable in Class I, Division 1.

• Identify the special article before using a general rule.

Renewable-energy questions center on PV rapid shutdown, DC conductor suitability, disconnects, interconnection, energy storage, markings, and simple current/voltage calculations. Pay special attention to multiple sources and to temperature effects on PV open-circuit voltage.

• Treating rapid shutdown as ordinary branch-circuit overcurrent protection.

• PV voltage: series adds voltage; parallel adds current.