NYY Cables Selection Guide
NYY cable is a 0.6/1 kV power cable with copper conductors, PVC insulation and a PVC sheath (TSE designation YVV). Type code, core and cross-section reading, selection steps.
What is NYY cable? NYY cable is a power cable with copper conductors, PVC insulation and a PVC outer sheath, rated at 0.6/1 kV; its TSE designation is YVV. It is used underground, in cable trunking and in outdoor fixed power distribution lines.
This guide covers what to look at when choosing products in the NYY Cables category.
How to read the NYY type code and product name
NYY is the type code in the German VDE designation: the leading N indicates the standard type, the first Y the PVC insulation and the second Y the PVC outer sheath. The YVV that appears next to it in product names is the TSE designation of the same cable. The manufacturer data cites the TS IEC 60502-1 standard for this cable.
The size after the code gives the number of cores and the conductor cross-section of each core.
- 4x10 mm²: four cores, each with a 10 mm² cross-section.
- 1x240 mm²: single-core cable; a separate cable is run for each conductor of the line.
- 3x240+120 mm²: three cores with a 240 mm² cross-section and a fourth core with a 120 mm² cross-section, written after the plus sign.
In manufacturer tables, the abbreviation next to the cross-section gives the conductor construction: re is solid (YVV-U), rm is stranded (YVV-R) round conductor, and se and sm are sector-shaped conductors. The -J added to the code in VDE data sheets indicates that one of the cores is a green-yellow protective conductor, and -O indicates that there is no green-yellow core. These details are not written in the product name; if core colors or conductor construction matter, see the manufacturer's data sheet.
How to determine the number of cores
The number of cores is determined by the number of phases of the line and by whether the neutral and protective conductors will be carried in the same cable.
- Single-core: phase, neutral and protective conductors are run in separate cables; common in main supplies with large cross-sections.
- 2-core: single-phase lines carrying phase and neutral.
- 3-core: single-phase lines with phase, neutral and protective conductors. In three-phase use it carries only the phases; the protective conductor is run separately.
- 4-core: the fourth core next to the three phases is, depending on the mains type, the neutral, the protective or the combined PEN conductor.
- 5-core: three phases, neutral and a separate protective conductor.
Constructions with a reduced fourth core, such as 3x240+120 mm², are for balanced loads where the neutral current stays below the phase current. For loads that generate harmonic currents, the loading of the neutral core is examined separately in the project calculation.
Which calculations verify the cross-section
The cross-section goes through three separate checks; the check that requires the largest cross-section determines the result.
- Continuous current. In manufacturer data, the permissible conductor operating temperature for NYY is 70 °C; current carrying tables give separate values for installation in the ground and in air. The cable current carrying capacity calculation tool offers a preliminary assessment for installation on surfaces and in conduit or trunking, and does not cover underground installation. For buried lines, the soil temperature, the thermal resistivity of the soil and the burial depth enter the calculation.
- Voltage drop. On long lines, a cross-section that is adequate for current may be insufficient because of the voltage loss at the end of the line. The voltage drop calculation tool shows this loss on single-phase and three-phase lines.
- Short-circuit withstand strength. In manufacturer data, the maximum short-circuit temperature is given as 160 °C for cross-sections up to 300 mm² and for durations not exceeding 5 seconds. The project calculation must show that the cross-section stays below this limit until the protective device opens the circuit.
The results of the tools are a preliminary check; the final cross-section is determined by the project calculation and the manufacturer's table.
Installation location and mechanical limits
NYY is an unarmored cable. Öznur Kablo defines its places of use as indoor and outdoor lines, underground and cable trunking where there is no excessive mechanical stress; on routes where mechanical damage is expected, protective measures are specified in the project. The same manufacturer gives the minimum bending radius for multicore NYY as 12 times the cable outer diameter; for large cross-sections, enclosure entries and bends are planned accordingly.
Difference between NYY and similar cables
- N2XH cables: have XLPE insulation and a halogen-free sheath. A comparison of the two types is in the article Difference between NYY and N2XH cable.
- N2XH FE180 cables: made for circuits that must keep their supply during a fire; NYY does not carry such a strength class.
- NAYY aluminum cables: the insulation and sheath are the same as NYY, the conductor is aluminum; the A in the type code indicates this. A larger cross-section than copper is needed for the same current.
- NYM Antigron cables: fixed installation cable for flush-mounted and surface-mounted use inside buildings; it is not used in place of NYY on underground lines.
- Flexible cables: NYY is for fixed installation. For connecting moving equipment, types with flexible conductors such as TTR are used, and for wiring inside enclosures, types such as NYAF.
Brands in this category
Koç Kablo, Win Kablo, Öznur Kablo, HES Kablo, Ünal Kablo, Nexans Kablo and Prysmian Kablo list NYY cable in this category in single-core and multicore constructions. The same size is often available from more than one brand; you can select the size with the Core Cross-Section filter and compare the brands on that size.
Ordering notes
- Cables are sold by the meter; enter the number of meters in the quantity field.
- Some of the products are listed as made to order; for these products the delivery time is confirmed before ordering.
NYY (YVV) Cable Cross-Sections and Application Selection Table
| NYY Cable Cross-Section | Core Structure and Voltage | Typical Protection / Current Range | Recommended Application | Category / Spec Link |
|---|---|---|---|---|
| 3x2.5 mm² – 3x4 mm² NYY Cable | Single-phase (L+N+PE) · 0.6/1 kV | 16 A – 25 A single-phase circuits | Landscape lighting, outdoor socket circuits and small pump feeders | 3x2.5 mm² NYY Cables |
| 4x4 mm² – 4x10 mm² NYY Cable | Three-phase + N/PE · 0.6/1 kV | 25 A – 50 A three-phase sub-panels | Sub-distribution boards, outdoor HVAC units and three-phase motors | 4x6 mm² NYY Cables |
| 4x16 mm² – 5x16 mm² NYY Cable | Three-phase (4 or 5 cores) · 0.6/1 kV | 63 A – 80 A building & workshop mains | Main building risers, construction site panels and underground feeders | 4x16 mm² NYY Cables |
| 3x35+16 mm² – 3x240+120 mm² NYY Cable | Reduced-neutral heavy power cable | 125 A – 400+ A main power distribution | Transformer-to-MDB feeders, industrial plant mains and utility trenches | NYY Cables |
Frequently asked questions
Are NYY cable and YVV cable the same product?
Yes. NYY is the type code in the German VDE designation; YVV is the TSE designation of the same construction. Both describe a 0.6/1 kV power cable with copper conductors, PVC insulation and a PVC outer sheath. Both codes are written together in the product names in this category. YVV-U is the solid-conductor construction and YVV-R the stranded conductor construction; what matters in an order is the number of cores and the cross-section.
How many amperes does NYY cable carry?
There is no single value; the current varies with whether the cable is laid in the ground or in air, the ambient or soil temperature, and the number of cables on the same route. As an example, the Öznur Kablo table gives 102 A in the ground and 79 A in air for 4x16 mm² NYY, and 188 A in the ground and 153 A in air for 4x50 mm². The table value is finalized in the project calculation with correction factors; for your own cable, see its manufacturer's table.
Can NYY cable be laid directly in the ground?
In manufacturer data, underground installation is listed among the places of use for NYY: Prysmian cites use in the open, in cable trunking and underground, and Öznur Kablo defines places without excessive mechanical stress. The cable is unarmored. Installation details such as burial depth, sand bedding, mechanical protection and warning tape are matters for the project and the applicable installation regulations; the work is carried out according to them.
What is the difference between 4-core and 5-core NYY cable?
A four-core cable has one more core next to the three phases; depending on the line configuration, this core is used as the neutral, the protective or the combined PEN conductor. In a five-core cable, the neutral and the protective conductor are separate cores. The mains type and the arrangement of the neutral and protective busbars in the enclosure determine which one is required; check the project's single-line diagram.
When is N2XH chosen instead of NYY?
When the project specification calls for halogen-free cable. The insulation and sheath of NYY are PVC; N2XH has XLPE insulation and a halogen-free sheath. One is not substituted for the other based on cross-section alone: rated voltage, current capacity, installation environment and project conditions are compared together. If the supply must be maintained in a fire, a strength class such as FE180 is also required.