A feeder ends at the final branch-circuit overcurrent protective device, and two of its section numbers moved

Where feeders sit on the paper

The PSI content outline gives electrical feeders 3 of the 56 scored items on the journeyman NEC Knowledge portion and 3 of the 24 on the Calculations portion. On the knowledge half that is a light area. On the calculations half it is an eighth of the paper, behind only services and branch circuits.

Our 500-question bank tells a fuller story, because feeders cross areas the way they cross a building. Seventy-five of the 500 mention a feeder: 17 in conductor sizing, 17 in installation knowledge, 16 in load calculations, 11 in motors and 10 in grounding. That spread is the point, since a feeder item is usually an item about something else with a feeder in the stem.

The load calculation area alone holds 42 questions, and the feeder-flavored ones in it are some of the hardest in the bank. Six sit at difficulty 3 or 4 and every one turns on the feeder neutral, which is treated below. Both portions pass at 70 percent and are scored separately, and in fiscal year 2025 the calculations portion passed 1,301 of 6,328 candidates.

The definition sets both ends

Article 100 defines a feeder as all circuit conductors between the service equipment, the source of a separately derived system, or another power supply source and the final branch-circuit overcurrent protective device.

Read the two ends separately, because each eliminates a different wrong answer. The upstream end is a source, so conductors ahead of the service disconnect are service conductors under Article 230. The downstream end is the final overcurrent protective device in the branch-circuit sense, so a supplementary device inside equipment leaves the feeder running, and so does an overload relay.

Work it as a question about the device. Find the last overcurrent protective device protecting a branch circuit. Everything downstream of it is branch circuit, and everything upstream, back to the service equipment or the source, is feeder.

The 2026 edition changed one word in that definition, which now says overcurrent protective device to match a term this edition defined. The boundary stayed put, and the current wording is what an item will quote at you.

The section numbers inside Article 215 moved

This is the change most likely to cost you time, because the article is small and both sections carrying the work slid.

Two of those numbers hold something different from what they used to hold. In a 2023 book, 215.4 is the common neutral section and 215.5 is diagrams. In a 2026 book those same numbers carry the minimum size rule and the overcurrent rule. All four addresses are occupied in both editions, which is slower to catch than a blank page, because you land on real code text that reads like an answer.

Everything from 215.6 upward kept its number: the feeder equipment grounding conductor at 215.6, ground-fault protection at 215.10, identification at 215.12.

Texas adopted the 2026 edition on 1 September 2026 under 16 TAC 73.100, and PSI references the examinations to it from the same day. A conflict is on the record: as read on 24 August 2026 the reference material list inside the PSI bulletin still named the 2023 edition, and so did TDLR's examination page, while the dated line in that same bulletin, updated 9 July 2026, names the 2026 edition. The dated line governs your appointment, and which code edition applies works through what to re-tab.

The 125 percent, stated twice

Article 215 states the increase in two sections, for two different objects.

• The conductor takes it at NEC 215.4. Where a feeder supplies continuous loads, or any mix of continuous and noncontinuous, the minimum conductor size has an ampacity at least equal to the noncontinuous load plus 125 percent of the continuous load.
• The overcurrent device takes it at NEC 215.5, and the arithmetic is the same: the device is rated at least the noncontinuous load plus 125 percent of the continuous load.

What it leaves alone is the load calculation. NEC 120.5(E) is new for 2026 and it releases a load calculation from carrying continuous loads at 125 percent, with a note explaining that continuous duty drives conductor size and device size, a separate question from how many volt-amperes the installation draws.

So a stem asking for a calculated feeder load and a stem asking for a minimum feeder conductor are two questions with two answers, separated by a quarter of the continuous portion. One bank question makes that concrete: a store's continuous lighting load of 24,000 volt-amperes on a 208Y/120 volt three phase feeder converts to 66.6 amperes, and the sizing rule then asks for 83.3. The option at 66.6 waits for whoever converted correctly and stopped.

The elimination worth carrying is the half-done option. An answer moving the conductor and leaving the device at the plain load has done half the rule. Branch circuit ratings works the same multiplier one level down.

The feeder neutral and its reductions

NEC 120.61 defines the feeder neutral load as the maximum unbalance, the largest net calculated load between the neutral and any one ungrounded conductor. A balanced three phase line-to-line load returns nothing through the neutral, so it adds nothing there. One bank question puts 60,000 volt-amperes of line-to-neutral load and 40,000 of three phase line-to-line load on a four wire feeder, and the neutral load is 60,000. The option at 100,000 belongs to whoever added everything on the feeder.

Three reductions live in that section and they stack in a fixed order.

• A dwelling range neutral is taken at 70 percent of the demand load already calculated for the ungrounded conductors. An 8,000 volt-ampere range demand gives 5,600 on the neutral.
• A dryer neutral is taken at 70 percent, after 120.54 has raised a 4,200 volt-ampere nameplate to the 5,000 volt-ampere minimum. The answer is 3,500, and the option at 2,940 belongs to whoever took 70 percent of the nameplate before applying the floor.
• The portion of an unbalanced load above 200 amperes takes a further 70 percent. A 260-ampere neutral becomes 242, since the first 200 stays whole and only the remaining 60 is reduced. The option at 182 belongs to whoever applied the factor to all of it.

That last reduction is withheld in two situations: a three wire circuit of two ungrounded conductors and the neutral taken from a four wire wye system, and the portion of the load that is nonlinear and supplied from a four wire wye system. Harmonic current on such a neutral fails to cancel between phases, so it can carry as much as the ungrounded conductors or more.

What a feeder question really is

Four shapes cover nearly all of them.

1. A calculated load in disguise, answered from Article 120. Demand factors decides more of these than Article 215 does.
2. A conductor sizing question, answered from the ampacity tables and the termination rating, with 215.4 setting the target.
3. A motor question, where the sum comes out of Article 430 and replaces the general approach. NEC 430.24 is the feeder conductor sum for a group of motors.
4. A classification question, where the whole item turns on whether the run described is a feeder or a branch circuit and the numbers are decoration.

The classification items are the cheapest points in the group and the easiest to lose, because they look like they need arithmetic and they need one sentence out of Article 100. One bank question sizes a feeder at 120 amperes by adding branch device ratings of 20, 20, 30 and 50, and the answer says the feeder is sized on the calculated load, since a device rating describes the most a circuit may draw.

The arithmetic for all four shapes sits in the question set, which answers the code question and shows the numbers. This page is about which shape you're holding and what a miss costs you.

What it costs on the job

Four rules genuinely live in Article 215, and three earn their keep on an inspection as much as on a paper.

Ground-fault protection of equipment at NEC 215.10 reaches a feeder disconnect rated 1000 amperes or more on a solidly grounded wye system of more than 150 volts to ground and at most 1000 volts phase to phase. The 2026 edition added a parallel subsection for solidly grounded dc systems above 150 volts to ground and at or below 1500 volts line to line.

Identification at NEC 215.12 catches more jobs than people expect. It applies where the premises wiring system has feeders supplied from more than one nominal voltage system, and it asks for each ungrounded conductor to be identified by phase or line and by system at every termination, connection and splice point. The trigger is written about the premises wiring system, so a single 480Y/277 volt feeder in a building that also carries 208Y/120 volts is caught.

Then there is the feeder that leaves the building. A feeder out to a detached garage needs a readily accessible disconnect at that building under Article 225, NEC 225.30 holds a building to one supply with named conditions permitting more, and where two supplies reach one building, NEC 225.37 asks for a plaque at each disconnect naming the other supply and its load.

What to do before test day

Three tabs and one habit.

• Tab 215.4 and 215.5 together and write the old numbers on the flag. If you practiced from 2023 material, your hand knows 215.2 and 215.3, and both now hold something else.
• Tab 120.61 on its own. The feeder neutral rules are where the difficulty 3 and 4 items live, and the section stacks three reductions that apply in a fixed order.
• Tab 120.5(E) beside 215.4. The multiplier question is the one candidates answer from habit, and habit was formed before this sentence existed.

The habit is one word written in the margin before you read the options: feeder or branch circuit. That word decides which article you open, and the classification items become free points once you make the call before the arithmetic tempts you. PSI accepts only tabs the code book publisher manufactured or provided.

Run the topic on a clock afterward. Thirty free timed questions will show whether you find 215.4 on the first turn of the page, and that is a measurable difference at 4.2 minutes an item.

Questions people ask

Where does a feeder start and where does it end?

Article 100 runs it from the service equipment, the source of a separately derived system, or another power supply source, up to the final branch-circuit overcurrent protective device. Both ends eliminate a wrong answer. Conductors ahead of the service disconnect are service conductors under Article 230. Downstream, the boundary is the last overcurrent protective device protecting a branch circuit, so a supplementary device inside equipment leaves the feeder running, and an enclosure with no overcurrent device in it leaves it running too.

What happened to NEC 215.2 in the 2026 edition?

Minimum Rating and Size moved from 215.2 to NEC 215.4, and Overcurrent Protection moved from 215.3 to NEC 215.5. The two numbers those sections took over were occupied: in a 2023 book 215.4 is Feeders with Common Neutral Conductor and 215.5 is Diagrams of Feeders, and those moved out to 215.14 and 215.13. All four addresses hold real text in both editions, so an old tab lands you on code that reads like an answer to your question and is answering a different one.

Do I apply 125 percent to a feeder load calculation?

The multiplier belongs to the conductor and the device. NEC 215.4 sizes the feeder conductor at the noncontinuous load plus 125 percent of the continuous load, and NEC 215.5 does the same for the overcurrent device. The load calculation itself is released from that by NEC 120.5(E), which is new in the 2026 edition. So a question asking for a calculated feeder load and a question asking for a minimum feeder conductor give two different numbers, separated by a quarter of the continuous portion.

How is a feeder neutral load calculated?

NEC 120.61 defines it as the maximum unbalance, the largest net calculated load between the neutral and any one ungrounded conductor, so a balanced three phase line-to-line load adds nothing. Three reductions then apply in order: dwelling range and dryer neutrals at 70 percent of their already calculated demand, and a further 70 percent on the portion of the unbalanced load above 200 amperes. That last one is withheld for nonlinear load from a four wire wye system and for three wire circuits taken from one.

How many feeder questions are on the Texas journeyman exam?

The PSI content outline gives electrical feeders 3 of the 56 scored items on the NEC Knowledge portion and 3 of the 24 scored items on the Calculations portion. That understates the real exposure, because feeder arithmetic appears inside conductor sizing, motor and service items as well. In our 500-question bank, 75 questions mention a feeder and they spread across seven subject areas, which is why feeder work pays back beyond the three items with its name on them.

Does a feeder to a detached garage need its own disconnect?

Yes. Article 225 carries the requirement for buildings supplied by a feeder or a branch circuit, and it asks for a readily accessible disconnect at the building being supplied. The upstream overcurrent device back at the house protects the conductors, and this rule is about control: somebody working in the garage has to be able to kill everything in it without walking to another building, and a firefighter needs the same. NEC 225.30 also holds a building to one supply, with named conditions permitting more.