Binder Tape: Not EI

Do not treat a binder as primary cable insulation. The phrase non woven binding tape electrical insulation can hide two different questions: does the tape avoid an unwanted conductive path, and is it qualified to serve as the cable’s primary insulation? A polyester nonwoven binder may secure and separate laid-up cores, but that does not by itself establish an insulation rating.

Is Non Woven Binding Tape Electrical Insulation?

The engineering answer is: only for the function and conditions supported by the cable drawing and verified data. A binder normally wraps a core assembly to maintain shape, separation and processing stability. The conductor insulation, by contrast, is the specified dielectric layer immediately surrounding the live conductor. These layers can both be described as “insulating” in casual language while carrying very different design responsibilities.

Conceptual blueprint; not a Chaowang cable drawing or product photograph.

This distinction matters because IEC 60502-1 addresses construction, dimensions and testing of power cables with extruded solid insulation. A material-level electric-strength method such as IEC 60243-1 answers a narrower test question. Neither a polyester composition nor a white appearance substitutes for cable-design qualification.

Separate Binding, Non-Conductive and Dielectric Functions

Before issuing an RFQ, define the required layer role. Four terms that sound similar should not be treated as interchangeable:

• Binding: holding laid-up cores or other components in a controlled, compact assembly.
• Separation: reducing direct contact or unwanted adhesion between adjacent cable layers.
• Non-conductive: describing a product category intended not to perform a semi-conductive screening function; this still needs an agreed property limit when electrically critical.
• Electrical insulation: a defined dielectric duty that must be supported by relevant properties, thickness, conditioning and system-level tests.

Conceptual layer-role blueprint; layer duties must follow the approved cable design.

The Chaowon non woven tape range includes products for different layer functions, so the location in the construction is as important as the generic material name. The CW-1 non-woven binding tape should therefore be assessed against its intended binding and separating role, not confused with a semi-conductive screen or automatically promoted to primary conductor insulation.

What the Public CW-1 Data Establishes—and What It Does Not

The current CW-1 page identifies a polyester-fiber and adhesive composition and publishes grade data for mass per unit area, thickness, tensile strength, elongation, short- and long-term stability, and moisture content. Those fields help engineers compare physical grades and assess processing suitability.

The same public table does not publish dielectric strength, breakdown voltage, volume resistivity, surface resistivity, relative permittivity, dissipation factor or a cable voltage-class approval. This absence does not prove that the tape has poor electrical behavior. It means the public page alone is insufficient evidence for a specified dielectric claim. For example, IEC 62631-3-1 defines a DC method for volume resistance and resistivity, but a standard title is not a test result for a particular grade.

Function-specific products also require separate evidence. A swellable layer such as CW-5 water-blocking tape is chosen for moisture-migration control; its water-blocking role does not establish the electrical duty of CW-1. Procurement documents should keep these layer functions separate even when both products use a nonwoven carrier.

How to Verify a Cable Binder Before Approval

Use a drawing-led review rather than accepting a broad material description. A practical approval sequence is:

Conceptual verification workflow; not a Chaowang laboratory record or qualification certificate.

1. Mark the layer position. State whether the tape wraps laid-up insulated cores, sits beneath a sheath, separates a metallic component or interfaces with a screen.
2. Define the required function. List binding, separation, cushioning, thermal exposure and any electrical limit as separate requirements.
3. Request current evidence. Ask for the applicable datasheet, grade identification, test method, specimen thickness, conditioning, electrode arrangement and acceptance limit when dielectric or resistive data are required.
4. Check adjacent materials. Confirm compatibility with insulation, filling compounds, screens and sheath materials under the intended processing and service conditions.
5. Run a representative line trial. Observe wrap stability, edge behavior, breakage, dust, overlap control and the condition of the assembly entering the next process.
6. Test the completed construction. Apply the cable specification’s required electrical, dimensional, thermal and mechanical checks; a material coupon cannot qualify the entire cable.

Jiangsu Chaowang New Material can review the cable drawing and proposed CW-1 grade. Send the layer position, cable type, tape width and thickness target, line conditions, adjacent compounds, applicable standard and required test evidence so the discussion starts from a measurable specification.

Frequently Asked Questions

Can CW-1 replace XLPE, PVC or another conductor-insulation compound?
CW-1 should not be assumed to replace an extruded conductor-insulation system. Its public information describes a polyester nonwoven binding product and lists physical properties, but it does not publish a voltage rating or the full dielectric dataset needed for that substitution. Follow the approved cable drawing and request a technical review for any change of layer function.

Does “non-conductive” automatically mean “electrical insulation”?
No. “Non-conductive” may distinguish a binder from a semi-conductive tape, but an insulation claim needs defined limits and test conditions. Ask what property was measured, by which method, at what specimen thickness and after what conditioning. The acceptable value also depends on the tape’s exact position and duty in the cable.

Which electrical properties should a buyer request?
Request only properties required by the design. These may include electric strength or breakdown voltage, volume and surface resistivity, and—where relevant—permittivity or dissipation factor. Specify units, method, conditioning and acceptance criteria. Do not copy a test list from another cable type without confirming that it answers the actual interface risk.

Must every binding tape be semi-conductive?
No. The required electrical behavior follows the layer location. A general binder around laid-up insulated cores may be specified as non-conductive, while a layer associated with an electrical screen may need controlled semi-conductive performance. Substituting one category for the other without reviewing field-control and interface requirements can change cable behavior.

Can one binder grade be used in both optical and power cables?
Possibly, but a shared material name is not approval. Optical and power constructions can impose different requirements for tensile behavior, thickness, moisture, cleanliness, thermal exposure, compatibility and electrical properties. Compare the two drawings, request the current grade data and validate a sample in the actual process before standardizing the material.

What is the minimum practical sample-approval package?
Start with the current datasheet, grade and lot identification, agreed certificate fields, and a sample in the intended width and roll format. Record the winding setup and line observations, then inspect the built cable and complete the required finished-cable tests. Retain the approved sample and conditions as the purchasing reference.

Need a defensible answer to a non woven binding tape electrical insulation requirement? Share the cable cross-section, layer duty and required electrical limits with Chaowon, then request the current datasheet and a representative CW-1 sample for line and finished-cable verification.