⚡ Measurement of insulation thickness of electric and optical fibre cables for the most common insulating compounds (cross-linked, PVC, PE, PP) — thin slice of insulation cut perpendicular to the conductor axis, measuring microscope or profile projector of at least 10× magnification or optical digital image analyser, reading 0,01 mm, six radial measurements, the first at the thinnest point, indented marking excluded from the mean, PN-EN 60811-201

Electronics and EMC PN-EN 60811-201

Overview

WHAT THE STANDARD COVERS. The PKN catalogue card of PN-EN 60811-201:2012 (Polish version) gives the scope: “This Part 201 of IEC 60811 gives the methods for measuring the insulation thicknesses which apply to the most common types of insulating compounds (cross-linked, PVC, PE, PP, etc.)” (our translation from the Polish text of the card). We read the text in the sample of IEC 60811-201:2012+AMD1:2017+AMD2:2023 CSV (edition 1.2, 2023-11, redline version: additions in green, deletions in red) — the sample covers the whole text of the standard, Clauses 1–5 and Figures 1–6; we read the changes from the images of pages 6 and 7. For comparison we also read the sample of IEC 60811-201:2012 (edition 1.0). The standard refers to IEC 60811-100:2012 (general requirements of the series), which we did not read here.

ACCORDING TO THE TEXT OF IEC 60811-201:2012+AMD1:2017+AMD2:2023 (foreword, introduction, Clauses 1–5, Figures 1–6). Edition 1.2 combines the first edition (2012-03) with amendment 1 (2017-07) and amendment 2 (2023-11); the standard was prepared by IEC TC 20 “Electric cables”; according to the foreword there are no technical changes with respect to the previous edition — it refers to the foreword of IEC 60811-100:2012; Part 201 is used together with IEC 60811-100. Introduction: the IEC 60811 series gives test methods for non-metallic materials of all cables, to be referred to in standards for cable construction and materials (insulation, sheaths, fillers, tapes); the methods were developed for energy cables but are also widely used for optical fibre, communication, control, shipboard and offshore cables. Scope (1): methods for measuring insulation thickness for the most common insulating compounds (cross-linked, PVC, PE, PP etc.). Reference (2): IEC 60811-100:2012; terms (3) from IEC 60811-100. General (4.1): use together with IEC 60811-100; the sentence “unless otherwise specified, tests shall be carried out at room temperature” has been deleted by the amendments; measurement of insulation thickness may be an individual test or a step in other tests (e.g. mechanical properties); the method of selecting samples — according to the cable product standard. Equipment (4.2): measuring microscope or profile projector of at least 10× magnification or an optical digital image analyser; the equipment shall allow a reading of 0,01 mm; for insulation with a specified thickness of less than 0,5 mm the reading is estimated to the third decimal place; in case of doubt the measuring microscope is the reference method. Samples (4.3): remove any covering from the insulation and withdraw the conductor (with separator, if any) without damaging the insulation; semi-conducting layers bonded to the insulation are not removed; the test piece is a thin slice of insulation cut along a plane perpendicular to the axis of the conductor; the cores of non-sheathed flat cables are not separated; with an indented marking (locally reducing the thickness) the test piece is taken so as to include it. Measurement (4.4): plane of the cut perpendicular to the optical axis; a) with a circular inner profile six radial measurements at approximately 60° (Figure 1), with sector-shaped cores six measurements according to Figure 2; b) insulation from a stranded conductor — six radial measurements according to Figures 3 and 4; c) uneven outer profile — according to Figure 5; d) unremovable screening layers under or over the insulation are excluded from the measurement; e) when such layers surround opaque insulation, a measuring microscope is used; f) flat non-sheathed cables — according to Figure 6, the insulation thickness in the direction of the other core being taken as half the distance between the conductors. In all cases the first measurement is taken at the thinnest point of the insulation. Indented marking is not included in the measurements used to calculate the mean thickness; in all cases the thickness at the position of the marking shall meet the minimum requirement of the product standard (the amendment replaced “in any case” here with “in all cases”). Readings in millimetres to two decimal places for a specified thickness of 0,5 mm and above, to three estimated places for smaller thicknesses. Evaluation (4.5): according to the requirements of the cable product standard. Test report (5): according to IEC 60811-100; after the amendments it includes the type of equipment used (microscope, profile projector or optical digital image analyser) and the magnification used — instead of the earlier “measuring equipment specifications”. Figures 1–6 (tm — minimum thickness): circular inner profile, sector-shaped conductor, stranded conductor (two figures), uneven outer profile, two-core flat non-sheathed cable.

STATUS (PKN catalogue cards as of 02.10.2026). The card of PN-EN 60811-201:2012 (Polish version, published 15-11-2021, 14 pages, price group G) has no “Withdrawn” heading: Electrotechnical Sector, KT 53 Cables and Wires, ICS 29.060.20 and 29.035.01, “Introduces: EN 60811-201:2012 [IDT], IEC 60811-201:2012 [IDT]”, “Replaces: PN-EN 60811-1-1:1999 – Polish version, PN-EN 60811-1-1:1999/A1:2002 – Polish version”; additional information: the standard partly replaces PN-EN 60811-1-1:1999 for measurements of insulation thickness, and together with PN-EN 60811-100:2012, -202:2012, -203:2012 and -501:2012 replaces it completely. Amendments: PN-EN 60811-201:2012/A1:2018-02 (Polish version, published 22-12-2021, 5 pages; changes 4.1, 4.2, 4.4 and 5; introduces EN 60811-201:2012/A1:2017 and IEC 60811-201:2012/AMD1:2017) and PN-EN 60811-201:2012/A2:2024-03 (English version, published 08-03-2024, 10 pages; changes 4.2; introduces EN 60811-201:2012/A2:2023 and IEC 60811-201:2012/AMD2:2023) — both without the “Withdrawn” heading.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, data up to 17.09.2026, read 02.10.2026). The number 60811-201 appears in 7 records at 7 laboratories: AB 044, AB 207, AB 261, AB 1776, AB 1814, AB 1917, AB 1974. In the current scopes on the PCA website (read 02.10.2026, issues from 10.10.2025 to 18.08.2026) all seven laboratories give the 2012 edition together with both amendments: in Polish notation (AB 261 — PN-EN 60811-201:2012, /A1:2018-02, /A2:2024-03; AB 207 — the same with the EN and IEC numbers in brackets; AB 044 — PN-EN, EN and IEC in the form “+A1+A2”) or in IEC notation only (AB 1776 and AB 1974 — IEC 60811-201:2012, 2012-03/AMD1:2017-07, 2012-03/AMD2:2023-11; AB 1917 — IEC 60811-201:2012, +AMD1:2017, +AMD2:2023; AB 1814 — “IEC 60811-201:2012+AMD1:2017+AMD2:2023” split over two lines in the PCA document, which is why a search for the number in the text of that document does not find it). In none of these scopes are the lines marked as suspended. The “Laboratories” tab shows 3 laboratories under “PN-EN 60811-201” (AB 044, AB 207, AB 261) and 5 under “IEC 60811-201” (AB 044, AB 1776, AB 1814, AB 1917, AB 1974) — checked with the tab query on the production server labcoda.pl on 02.10.2026.

WHAT THE LABORATORIES TEST (PCA entries). AB 044 — power cables and wires: insulation thickness (next to PN-EN 50396 and PN-HD 605). AB 207 — cables and wires of rated voltage up to 18/30 kV and outer diameter up to 100 mm: linear dimensions — insulation thickness (0–50) mm, thickness of non-metallic sheaths (0–50) mm, outer dimensions (0–300) mm. AB 261 — cables and wires with the same limits: checking the construction and dimensions of components. AB 1776 and AB 1974 — cables: insulation and sheath thickness (0,01–40) mm (next to ISO 19642). AB 1814 — cables: insulation and sheath thickness (0,01–25) mm (next to ISO 6722, ISO 19642 and DIN/TS 70112-1). AB 1917 — cables and cable accessories with Un = (3,6–500) kV: checks of construction and dimensions — conductor construction, insulation and sheath thickness, diameters (next to HD 620, IEC 60502-2, IEC 60840, IEC 62067 and IEC 60228).

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. First measurement: in all cases it is taken at the thinnest point of the insulation (4.4). Indented marking: the test piece shall include it (4.3), but it is not included in the mean, and the thickness at that point is checked separately against the minimum of the product standard (4.4). Thin insulation: below 0,5 mm the reading is estimated to three decimal places (4.2, 4.4). Screens: unremovable screening layers are excluded from the measurement, and with opaque insulation a measuring microscope has to be used (4.4 d, e). Flat cables: the thickness in the direction of the other core is half the distance between the conductors (4.4 f). Dispute: the reference method is the measuring microscope (4.2). Test report: after the amendments it has to state the type of equipment and the magnification (5). Temperature: the sentence about testing at room temperature was deleted — conditions have to be taken from IEC 60811-100 and the product standard.

WHAT WE DO NOT STATE. We did not read IEC 60811-100 — so we do not state the general requirements of the series (conditioning, test temperature, number of samples). We do not state the required insulation thicknesses or how the result is calculated — according to 4.5 they follow from the cable product standard. We do not attribute individual text changes to amendment A1 or A2 beyond what the PKN cards state (A1: 4.1, 4.2, 4.4, 5; A2: 4.2).

Method principle

A thin slice of insulation is cut from the cable core in a plane perpendicular to its axis and measured under a measuring microscope, a profile projector (at least 10×) or an optical digital image analyser with a reading of 0,01 mm — usually six radial measurements, the first at the thinnest point; from the readings the mean thickness (without indented marking) and the minimum thickness are determined and evaluated according to the cable product standard.

Applications

• Power cables and wires, including medium and high voltage (up to 500 kV) — checking construction and dimensions; 7 laboratories in PCA scopes
• Cables tested together with automotive cable standards — next to ISO 19642 (AB 1776, AB 1974), and also ISO 6722 (AB 1814)
• A step in other tests of non-metallic cable materials (e.g. mechanical properties) that need the insulation thickness (4.1)

Key parameters

Standard

Standard number

PN-EN 60811-201:2012 (wersja polska; EN 60811-201:2012 i IEC 60811-201:2012 IDT) ze zmianami PN-EN 60811-201:2012/A1:2018-02 (wersja polska) i PN-EN 60811-201:2012/A2:2024-03 (wersja angielska)

Title (PL)

Kable i przewody elektryczne oraz światłowodowe — Metody badań materiałów niemetalowych — Część 201: Badania ogólne — Pomiar grubości izolacji

Title (EN)

Electric and optical fibre cables — Test methods for non-metallic materials — Part 201: General tests — Measurement of insulation thickness

Step-by-step procedure

1. Samples

   Selection of samples according to the cable product standard; remove coverings, withdraw the conductor without damaging the insulation, do not remove semi-conducting layers bonded to the insulation (4.1, 4.3). PN-EN 60811-201:2012 with A1 and A2 current (PKN cards as of 02.10.2026).

2. Slice

   Thin slice of insulation cut perpendicular to the conductor axis; with indented marking — including it; do not separate the cores of non-sheathed flat cables (4.3).

3. Measurement

   Plane of the cut perpendicular to the optical axis; six measurements according to Figures 1–6, the first at the thinnest point; exclude unremovable screens from the measurement (4.4).

4. Readings

   In millimetres to two decimal places (specified thickness ≥ 0,5 mm) or to three estimated places (< 0,5 mm); indented marking excluded from the mean and checked separately against the minimum (4.4).

5. Evaluation and report

   Evaluation according to the cable product standard (4.5); report according to IEC 60811-100 with the type of equipment and magnification (5).

Required equipment and apparatus

Health and safety (OHS)

• In the text of Part 201 the standard gives no safety requirements

Frequently asked questions