Korean Electrician Control-Panel Layout — 400×420 Board and ±5mm Tolerance
Every part you met in L1–L8 (MCCB + fuse, EOCR, MC, 8-pin relay, timer, push-buttons, lamps, terminal blocks) now goes onto a single sheet of plywood — the control panel. But before any wire is drawn, where and how you place the parts is already graded. Get the positions wrong and you can be disqualified outright.
Board size & tolerance
- Board — 400 mm wide × 420 mm tall.
- Inside the board (parts on the plywood) — ±5 mm from the drawing. Eyeballed placement loses points sharply.
- Outside (conduit · boxes · cable · off-panel terminals) — looser, ±30 mm.
Four placement principles
- Left/right symmetry — heavy parts (MCCB · MC · EOCR) and their paired controls (PB / LAMP clusters) mirror around the centerline.
- Rows & columns align — same kind on the same row, same category in the same column. Follow the placement drawing and its specified dimensions.
- Terminal blocks at the edges — the incoming input block on the left edge, the outgoing output block on the right edge, so external conduit and cable exit cleanly through the side.
- Keep the wiring lanes — leave a horizontal channel between part rows and the vertical wiring margins shown in the particular layout. These empty lanes are where the next step's wires run at right angles.
Next
Once the parts sit by the rules, the wires that join them have rules of their own — Wiring rules: max 2 wires per terminal, right-angle routing, route-via.
Try it yourself
Open the practical project list →
Check your understanding
Question: Can every dimension be measured from a component edge?
Answer: Read the drawing datum first. The cited exam instructions use the component center where a datum is not otherwise specified.
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.
Worked measurement check
Suppose the drawing places a component center 100 mm from a stated datum. Centers measured at 103 mm and 107 mm differ by +3 mm and +7 mm. Against a ±5 mm target, only the first falls inside the band. Moving the ruler to a nearby component edge changes the datum and invalidates that comparison. This checks one dimension only; it does not predict a total score or replace the official disqualification criteria.