Litz Wire

Served Litz Wire — QAUSSuperior Stability & Mechanical Protection

Served with natural silk, polyester, or nylon for unparalleled dimensional stability and easy post-processing.

Serving is the process of helically wrapping one or two layers of textile yarn around a finished litz wire bundle under controlled tension. The serve locks individual strands into their transposed positions, preventing them from shifting during handling, winding, or operation — preserving the precise strand geometry that gives litz wire its electrical properties.

Three serving materials are available, each suited to different operating conditions. Natural silk offers the lowest dielectric constant (εr ≈ 1.4), making it the preferred choice for RF-sensitive applications. Nylon provides the best elongation range (25–46%) for superior flexibility in tight winding geometries. Polyester delivers the lowest moisture absorption (0.2–0.5%), ideal for humid or outdoor environments. A single serve adds approximately 0.05mm to the outer diameter.

Dimensional Stability

The helical textile wrap locks strands into a fixed geometry, preserving the precise transposition pattern that gives litz wire its low AC-loss properties.

Splice Prevention

When cut, released twist energy can cause strands to spring apart ("bird-caging"). The serve contains this energy, keeping cut ends intact for clean termination.

Serving Material Options

Silk (lowest εr at 1.4, ideal for RF), nylon (best flexibility at 25–46% elongation), or polyester (lowest moisture absorption at 0.2–0.5%).

Mechanical Protection

Protects thin enamel insulation from abrasion during winding onto bobbins or through tight slots — critical for maintaining strand-level isolation.

Available with 5 to 2,000 strands and single wire diameters from 0.04mm to 0.8mm in single-serve or double-serve configurations. Common applications include HF transformers, resonant converters, inductive charging coils, and chokes where the wire undergoes significant mechanical stress during assembly.

Technical Specifications

Served Litz Wire Specifications

QAUS — Served Litz Wire with natural silk, polyester, or nylon serving.

Number of Strands	Single Wire (mm)	Single Wire (AWG)	Outer Diameter (mm)	Outer Diameter (AWG)
5 – 2000 pcs	0.04 – 0.8	#20 – #46	0.2 – 4.2	#6 – #32

Applications

Served litz wire is used in HF transformers, resonant converters, inductive charging coils, chokes, and any application where the wire undergoes significant mechanical stress during assembly. The textile serving is particularly valuable when winding through tight slots, around sharp edges, or onto automatic winding equipment where strand displacement would degrade high-frequency performance.

Frequently Asked Questions

What serving materials are available for litz wire?+

YIDA offers three serving materials: natural silk (lowest dielectric constant at 1.4, ideal for RF applications), nylon (best flexibility with 25-46% elongation for tight winding geometries), and polyester (lowest moisture absorption at 0.2-0.5%, suited for humid or outdoor environments). Single-serve and double-serve configurations are available.

When should I choose served litz wire over basic litz wire?+

Choose served litz wire when the winding process involves mechanical stress that could displace strands from their transposed positions — such as pulling through slots, bending around sharp corners, or high-speed automatic winding. The serve locks strand geometry in place, maintaining the AC loss performance that basic litz wire achieves only when strands remain properly transposed. Basic litz wire is preferred when maximum flexibility and smallest diameter are the priority.

Does textile serving affect the electrical properties?+

The textile serving itself does not significantly affect conductivity or AC loss performance — it is an outer mechanical layer. However, by preserving proper strand transposition during handling and winding, the serve actually helps maintain the designed AC loss characteristics. The serve material does contribute a small amount to the overall dielectric constant, which is why natural silk (lowest dielectric constant) is preferred for RF-sensitive applications.

What is the maximum number of strands for served litz wire?+

YIDA produces served litz wire with up to 2,000 individual strands. Single strand diameters range from 0.04mm (#46 AWG) to 0.8mm (#20 AWG). A single layer of textile serving adds approximately 0.05mm to the overall outer diameter. For higher strand counts or special requirements, contact our engineering team to discuss your application needs.

YIDA Wire has manufactured enameled copper wire since 1984. IATF 16949, ISO 9001, and UL certified. Trusted by industry leaders across 50+ countries. Contact us for specifications →