Dutch cable types: VD, XMvK, YMvK and underground cable

Start with the intended use: an existing conduit route, a new indoor installation or a supply through the garden. Have the cable family, conductor count and cross-section specified before ordering. A familiar name or a discounted reel does not establish suitability.

What the four names describe

VD installation wire is an individually insulated conductor. Its construction differs from a cable containing several insulated cores within an outer sheath. Nexans specifies conduit or a similar closed system for its H07V-U/H07V-R Eca installation wires.

XMvK is a light installation-cable family. TKF describes its XMvK Eca for fixed individual connections. Check the exact product's restrictions, including bundling, heat and exposure.

YMvK is an installation-cable family with different product applications. For example, Nexans publishes a particular construction and fire classification for YMvK Dca ULTIMO. Those properties cannot be assigned to every grey cable.

YMvK-as and related underground-cable constructions have a different build. A specific product may permit direct burial: TKF states this for the linked VO-YMvKas model. That does not settle the route, protection, terminations or protective-earth arrangement.

Read beyond the family name

Check the datasheet for:

• the full designation and manufacturer part number;
• core count and conductor colours or functions;
• conductor cross-section in mm² and conductor class;
• outside dimensions and bending or installation restrictions;
• moisture, sunlight, temperature and mechanical properties;
• fire classification and the relevant declaration of performance.

A value in mm² describes a conductor's cross-sectional area. It is not the outside diameter of the complete cable. An additional sheath or screen can increase the cable's overall size without changing the chosen conductor area.

Check how any earth conductor or screen is identified in the description. A shortened shop title cannot establish which protective conductor is present or how it must be terminated.

How is the conductor size chosen?

The required size depends on more than the appliance's power rating. Length, protection, installation method, surrounding conditions and other factors affect the assessment. Prysmian lists several design inputs for cable calculation.

The material-length tool accompanying this guide therefore calculates metres only. It does not select conductor size or assess voltage drop, fault withstand or protective devices. Have those decisions recorded before choosing among products with similar names.

Avoid treating the dimensions of an old cable as proof of what the replacement should be. The previous installation may have different loads, conditions or unresolved defects.

Prepare a useful order schedule

1. Describe the equipment being supplied and record its manufacturer information.
2. Draw the complete route, including vertical sections and termination points.
3. Record the conditions along each part: indoors, outdoors, in conduit, through insulation or in the ground.
4. Have the electrical specification and termination method confirmed.
5. Calculate the required length and compare suitable purchase quantities.

For a conduit system, count the separate conductors according to the agreed schedule. For a multicore cable, measure the length of the complete cable. Keep agreed termination allowances visible. Deduct only existing stock that is identifiable, serviceable and suitable for the design.

A reel-size calculation cannot compensate for a route that has not been surveyed. Keep any uncertain section marked separately and resolve it before ordering cut-to-length material.

Include the associated materials

A complete list may include conduit, supports, boxes, glands, connectors and identification. For a ground route, the ground conditions, protection and accessible terminations also need attention. The design determines those items and quantities; one reel and two boxes will not be a complete kit for every project.

After confirming the specification, compare cables at Elektramat or underground-cable categories at HORNBACH. Check the exact variant before purchase. An “outdoor cable” category is not proof of direct-burial suitability.

Frequently asked questions

Is 2.5 mm² always correct for a socket circuit?

No. The installation and its conditions determine the required specification. A commonly sold size is not a universal design rule.

Is grey cable automatically underground cable?

No. Check the manufacturer’s data for the exact product. Colour is not a reliable selection method.

Can I use leftover cable?

Only when its type, condition, length and origin are sufficiently known and it suits the confirmed design.

Would you like the material choice checked first? Discuss the route and application with CAS. Mention any cable you already own without assuming it must be used.