IEC 60502-1:2021 (Edition 3.0) covers extruded power cables for fixed installations at two voltage ratings, 0.6/1 (1.2) kV and 1.8/3 (3.6) kV, while IEC 60502-2:2014 (with Amendment 1 published 2024) covers the next range, from 3.6/6 (7.2) kV up to 18/30 (36) kV [S2][S1][S5]. The two parts together span the common 1 to 30 kV distribution band and form the reference cited by most utilities and industrial buyers.
The boundary is sharp: Part 1 ends at Um = 3.6 kV, Part 2 begins at Um = 7.2 kV. Nothing in the family covers 3 kV to 6 kV as a standard rating, so any cable specified between those values is effectively built either as a 3 kV class to Part 1 or as a 6 kV class to Part 2 [S3][S4]. For specifiers working through a power cable tender, the first decision is the Um value, not the cable maker or the armour type.
Voltage scope: the five ratings that define each part
IEC 60502-1 lists two U0/U(Um) ratings, 0.6/1 (1.2) kV and 1.8/3 (3.6) kV, both with extruded solid dielectric and fixed installation on distribution or industrial networks [S2][S4]. IEC 60502-2 lists five ratings, 3.6/6 (7.2) kV, 6/10 (12) kV, 8.7/15 (17.5) kV, 12/20 (24) kV, and 18/30 (36) kV, the last being the upper limit of the entire IEC 60502 family [S1][S3][S4].
There is a 0.6 kV class, 1 kV class, and 3 kV class under Part 1. There is no 0.6/0.6 kV or 0.3/0.6 kV rating in either part; low-voltage control and instrumentation work at those levels falls under different publications. The family also explicitly excludes overhead lines, mining, nuclear containment areas, submarine links, and shipboard cable [S1].
Construction differences: insulation, screen, and armour
Part 1 permits PVC/A (70 deg C), EPR, HEPR, and XLPE (90 deg C) insulation, with thermoplastic sheaths PVC ST 1/ST 2, polyethylene ST 3/ST 7, halogen-free ST 8, plus elastomeric SE 1 (polychloroprene, chlorosulfonated polyethylene) [S4]. Conductor sizes run 1.5 mm squared to 1,000 mm squared, in Class 1 solid, Class 2 stranded, or Class 5 flexible per IEC 60228 [S4].
Part 2 extends the size range to 10 mm squared through 1,600 mm squared and keeps Class 1 and Class 2 only, no flexible Class 5, because medium-voltage cables are not built for repeated flexing [S3][S4]. Insulation options are similar (XLPE 90 deg C, EPR/HEPR 90 deg C, PVC/B 70 deg C for 3.6/6 kV only), but every Part 2 cable carries a metallic screen plus a semi-conductive layer on conductor and insulation, neither of which is mandatory at 1 kV [S4][S5].
Armour and metallic layer options are described in both parts, lead or lead alloy sheath, concentric conductors, wire or tape armour, or unarmoured, with single- and multicore constructions covered across the family [S3][S4]. For readers mapping this against the broader power distribution chain, the screen is the part that changes the most across the 1 kV to 30 kV jump.
Test requirements: routine, type, sample, and the after-install check
Both parts run a routine voltage test on every drum, plus type tests on the design and sample tests on materials, but Part 2 adds partial discharge (PD) testing on the insulation screen and a 0.1 Hz test after installation, the latter being one of the technical changes introduced in the 2014 third edition of IEC 60502-2 [S1][S5]. A 0.1 Hz after-installation test is also permitted on Part 1 cables, but the dielectric withstand on a 6 to 30 kV cable is the gating step most failures are caught at.
Part 2 also added, in the third edition, a new subclause for a routine electrical test on the oversheath, a simplified calculation procedure for lead and oversheath thickness, modified tolerances for the bending test cylinder, and modified non-metal sheath and semi-conductive layer requirements [S1]. Those changes flow through to OD-5003-F1 in the IECEE CB test report forms, which now list IEC 60502_2B and IEC 60502_2C as the active TRFs against the 2014 base with Amendment 1 (2024) [S1].
Selection criteria: which part applies to a given load
Pick Part 1 when the system voltage is 1 kV or 3 kV class, three-phase 400 V or 690 V building or plant distribution, substation LV auxiliaries, or any fixed installation under 3.6 kV Um. Pick Part 2 when the system voltage is 6 kV to 30 kV class, MV feeders, ring mains, transformer LV-to-MV tails, or large motor leads at 6 kV or 11 kV [S3][S4][S5].
Material and chemistry choice is similar across the two parts (XLPE 90 deg C is the default for both), so the decision rarely turns on insulation type alone. It turns on three things: the Um value, the screening requirement, and whether PD-tested deliveries are required by the contract. For projects that cross 3.6 kV, the procurement note should explicitly state both the cable standard (Part 1 or Part 2) and the matching accessory standard, IEC 60502-4 for joints and terminations on the MV side, since mixing the two creates approval gaps at site [S5][S8].
Comparison matrix: Part 1 versus Part 2 on five decision criteria
Voltage range: Part 1 = 0.6/1 (1.2) kV and 1.8/3 (3.6) kV; Part 2 = 3.6/6 (7.2) kV through 18/30 (36) kV, five ratings [S1][S2][S4]. Conductor size: Part 1 = 1.5 to 1,000 mm squared, Class 1/2/5; Part 2 = 10 to 1,600 mm squared, Class 1/2 only [S4]. Conductor temperature: 90 deg C for XLPE/EPR/HEPR in both, 70 deg C for PVC, PVC/B at 3.6/6 kV only in Part 2 [S4]. Mandatory metallic screen: not required at 1 kV to 3 kV; required on every Part 2 cable above 6 kV [S4][S5]. Test additions: Part 2 adds partial discharge on the insulation screen and the 0.1 Hz after-installation test as a published option [S1][S5].
Typical applications: Part 1 fits power distribution inside buildings, plant LV switchgear, substation auxiliary feeds, fixed lighting and control power; Part 2 fits MV feeders, utility ring mains, large motor leads, and the cable between MV switchgear and transformers. Both exclude overhead, mining, nuclear, shipboard, and submarine [S1][S3].
Limitations, exclusions, and what neither part covers
Neither part covers fire performance, that is, flame spread, smoke, halogen content, and circuit integrity under fire, which live in IEC 60332-1-2, IEC 60332-3, IEC 60331 series, and IEC 61034 [S5]. Neither part covers DC above 1.5 kV between conductors or 0.9 kV to ground, IEC 60502-1 Part 1 cables rated 0.6/1 kV may be used in DC systems up to those limits, but anything above is outside scope [S4]. Accessories (joints and terminations) are not in either part: terminations and joints for Part 2 cables are governed by IEC 60502-4, not IEC 60502-1 or -2 [S5][S8].
Part 3 of the IEC 60502 family is reserved for future use, so any project reference to IEC 60502-3 should be treated as a misprint [S3].
Standards traceability: editions, amendments, and national variants
IEC 60502-1 is currently Edition 3.0, published 2021-02 [S2]. IEC 60502-2 is currently the third edition published 2014-02-20, with Amendment 1 issued in 2024, the working combination cited as IEC 60502-2:2014+AMD1:2024 across most industry guidance published in the second half of 2025 and into 2026 [S1][S5].
National variants still matter: China adopts GB/T 12706.2-2020 as the equivalent of Part 2 (last modified 2024-04-19), and Saudi Arabia uses SASO-GSO-IEC-60502-2 (last modified 2025-06-19) under the CENELEC group differences framework [S1]. For CENELEC members (the EU, EFTA, the UK, Türkiye, and the Balkans), Group Differences apply on top of the IEC text and must be checked before a procurement is let [S1].
For spec work on the cable, or for electronic test and measurement of cable runs after installation, the same rule applies: state the IEC part number, the year, and the amendment, and pair it with the relevant fire and accessory standards before the contract goes out. A 2026 factory acceptance test that calls out IEC 60502-1:2021 plus IEC 60332-1-2:2025, or IEC 60502-2:2014+AMD1:2024 plus IEC 60332-3:2018 and IEC 60331-4:2024 for life-safety circuits, is the working baseline seen in current tender documents [S5][S7].
See also our earlier report, IEC 60034-11 built-in thermal protection vs external overload relay: 2026 spec reality.