Craftsman Electrician study guide

Korean Electrician Conduit Finishing — Pipe, Saddles, and Pulling Wires

Last updated: 2026-10-05 · 5 min read

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Once the wiring *inside* the panel is done, one job remains — connecting the world outside the panel (the supply, motors, water tank, and the control boxes that hold the buttons and lamps) with cable and conduit. This conduit work is graded separately: not whether the circuit is correct, but whether the pipework meets spec. The ±30 mm tolerance for off-panel parts was covered in panel layout — here we cover the pipe, saddles, and wire-pulling that join them.

The conduit network between the boxes — straight runs (PE pipe) vs bends (flexible conduit), run dimensions, and saddle positions on one sheet.

The order — boxes first, wires last

Conduit work follows a fixed sequence.

Place the boxes — octagon JB + control boxes.
Conduit + terminal blocks + saddles — run pipe between the boxes, set the TBs at the pipe ends, clamp with saddles.
Power cable — bring the external supply to the panel's input TB.
Pull the wires — route them through the conduit you laid.

Just like the real job, you set the boxes first and run pipe between them (the trade order: chalk line → box → conduit). Wires go in last, after every pathway exists.

Two kinds of box — octagon JB and control box

Where the octagon JB, the control boxes, and the field terminal blocks (TB) sit relative to the panel.

Octagon junction box (JB) — where several conduit runs meet and branch. It is the junction box specified in this example; follow the actual drawing for box type and shape.
2-gang control box — an empty enclosure that holds buttons and lamps (electrically just a pass-through box), with ports top and bottom for conduit. A problem typically uses four of them; you seat PB (push buttons), RL·GL·YL (lamps), BZ (buzzer), SS (selector) into the slots — two per box, with the selector taking a slot on its own.

Two kinds of pipe — PE pipe on straights, flexible conduit on bends

Black rigid PE pipe (straight runs) and white flexible conduit (bends).

PE pipe (black, rigid) — straight runs.
flexible conduit (white, flexible) — bends.

Each run has a specified type you must respect. Swapping a flexible run for rigid, or a bend for rigid pipe, is a points/disqualification matter.

Saddles — check both the drawing and fixing criteria

The referenced problem-14 instructions (pages 11-2 and 11-4) require fixing near equipment connections, within 300 mm. An unbent run shorter than 400 mm between equipment ends has a one-saddle exception. Both saddle screws must be fastened for the fixing to count.

There is no universal rule that every terminal block needs saddles exactly 50 mm on either side. Start with the actual drawing and connection locations, then apply the stated criteria.

The power cable — one 4-core run

The single cable into the input TB and its cable-saddle spacing.

Pull one 4-core cable from the POWER source just off the top of the panel into the input TB (L1·L2·L3·PE). One jacket carries all four conductors (L1 brown · L2 black · L3 gray · PE green-yellow). Fasten it with two cable saddles.

Pulling the wires — routing conductors through the conduit

With the pathways laid, connect the panel terminals to the field devices, routing each wire through the conduit. Colors are unchanged — main circuit L1 brown · L2 black · L3 gray · PE green-yellow, control circuit yellow (wiring rules).

Selector (SS) — three contacts. The common is SS, branching to A (Auto) and M (Manual). Turning the switch ties the common to A or M, picking the auto / manual circuit.
Buzzer (BZ) — like a lamp, needs both a supply and a return path.

Common mistakes — disqualification points

Swapping a run's pipe type — keep PE pipe / flexible conduit matched to straight vs bend.
Skipping the octagon JB at a branch — every place pipe splits must go through the JB.
Ignoring saddle placement — check drawing dimensions, the stated distance limit and both fixing screws.
Wiring the cable straight into POWER — the cable must land on the input TB.

Try it yourself

Start from a blank board and take one problem all the way through — place the parts, wire the main circuit, wire the control circuit, then finish the conduit and pull the wires. Do that once and the whole practical clicks into place.

Open the practical project list →

Check your understanding

Question: When can one saddle be used on a 350 mm straight run?

Answer: The cited exception requires no bend and less than 400 mm between equipment ends. Check those conditions and secure fixing, not length alone.

Practice path and references

The practical project list may require sign-in. Create a project, choose a task and place the relevant components, then compare the contact/wiring paths explained here. The link does not preload a specific completed circuit.

Reference: Q-Net public-problem notice, 2025-08-04 edition, problem 14 pages 11-1 to 11-4 (work/wiring instructions) and 11-9 (component diagrams). Read the original for each task and any amendments. Site examples are distinct from general installation design requirements.

Compare two routes before fixing saddles

A 350 mm straight run may meet the cited one-saddle exception only when it is unbent and the measurement is between equipment ends. A 450 mm run does not meet that length condition; a bent 350 mm run does not meet the shape condition. Mark both connection points first, then apply the drawing and the fixing-distance requirements. Do not decide from the visible middle section alone.