§514 — Identification: labelling, warnings and documentation for the installation

The guide on conductor colours covers how individual conductors are recognised by their colour. §514 of NEN 1010 (based on IEC 60364-5-51) goes a step further: this provision governs not only the identification of conductors, but also of switching and protective devices, mandatory warning notices, and the documentation (diagrams, charts) that must be kept with an installation so that the next technician or inspector can understand it without guesswork.

What §514 covers

• Identification of conductors — colour and/or numbering, so that a line, neutral or protective conductor is unambiguously recognisable (see the conductor-colours guide for the details per conductor type).
• Identification of switching and protective devices — every circuit in a distribution board must carry a label indicating which part of the installation that circuit supplies, so a technician does not have to switch-and-observe to find the right circuit.
• Warning notices — among others, the notice indicating that an installation (or part of it) is protected by a residual current device, including a recommended test frequency, and a notice at installations with more than one supply source (for example a standby generator or a second connection point) that parts of an installation may remain live even without the main supply.
• Diagrams, charts or schedules — for installations that cannot be understood at a glance, documentation must be kept at the origin showing which circuits exist, which cross-section and wiring method was used, and which protective devices belong to each circuit.

Why this is more than paperwork

Identification and documentation are not a side issue next to the "real" safety measures (earthing, RCD, overcurrent protection) — they are the link that allows the next person to use those measures correctly. An RCD that functions perfectly but whose existence is not indicated at the origin may be overlooked in a later assessment during a renovation. A circuit without a label forces a technician, when isolating for safe work (step 3 of the five safety rules), to switch by guesswork, with the risk of switching off the wrong circuit.

Practical relevance

When a new installation or a major renovation is handed over, the distribution board should as standard carry legible, durable circuit labels, and — where applicable — an RCD test notice and a notice of any additional supply sources should be present. During a NEN 3140 periodic inspection, the absence of this identification is a common finding that, while not a direct shock hazard in itself, undermines the safety of future work on the installation.

Common mistakes

1. Not labelling circuits in the distribution board, or labelling them illegibly — handwritten labels that fade over time do not meet the requirement that identification must be durable.
2. Not fitting an RCD test notice even though the installation is in fact protected by a residual current device — the user then does not know that, or how often, the test button should be pressed.
3. Not adding a warning on an installation with a standby generator or second supply source that certain parts may remain live even without the main supply — a technician who only switches off the main switch could wrongly assume the installation is dead.
4. Not maintaining a diagram or circuit schedule after modifications — a distribution board that, after years of renovations, no longer matches the original diagram forces every subsequent technician into time-consuming and error-prone reverse-engineering of which circuit goes where.

Related

• Conductor colours
• Distribution board — circuit identification & reading the wiring diagram
• Two-pole voltage tester — proving dead
• LOTO — the five safety rules