IEC 60317 Glass Fiber Covered Enameled Rectangular Copper Wire
1. Scope And Definition
Applicable to copper conductors with rectangular cross-section, with bare copper or coated with varnish (such as polyester, polyimide, etc.).
The outer layer of the conductor is wrapped with glass fiber yarn and impregnated with resin or varnish to improve mechanical strength and heat resistance.
Mainly used in electrical insulation systems with high heat resistance grades (such as Class 155/F and above).
2. Dimensions
(1) Conductor size (bare copper or enameled)
Width (a): The standard range is usually 2mm ~ 16mm (see manufacturer specifications for details).
Thickness (b): The standard range is usually 0.8mm ~ 5.6mm.
Corner radius (r): The four corners of the conductor are rounded, and the radius is usually 0.3mm ~ 1.0mm (depending on the size).
(2) Glass fiber coating
Number of wrapping layers: single or multiple layers (such as 1~2 layers), depending on the insulation requirements.
Impregnation material: epoxy resin, polyester paint or high temperature resistant silicone resin.
Final insulation thickness: usually 0.1mm~0.5mm more than the bare conductor (depending on the number of wrapping layers and impregnation process).
(3) Tolerance requirements
Parameter Tolerance (typical value)
Conductor width (a) ±0.02mm~±0.1mm
Conductor thickness (b) ±0.02mm~±0.08mm
Total size after insulation ±(5%~10%)
3. Key Test Items
(1) Dimension detection
Width and thickness measurement (micrometer or optical measurement).
Corner radius inspection (projector or microscope).
(2) Electrical performance test
Conductor DC resistance (in accordance with IEC 60851-3).
Withstand voltage test (e.g. 3kV/1min, no breakdown).
Insulation resistance (≥100MΩ, 500V DC test).
Withstand Voltage Requirements (IEC 60317-0-5)
| Test Type | Test Voltage (RMS) | Duration | Pass Criteria |
| AC Voltage Test | 2.5kV – 3.5kV | 1 min | No breakdown, leakage <1mA |
| DC Voltage Test | 1.5kV – 3.0kV | 1 min | No breakdown or arcing |
| Short-Time Test | 3.5kV – 5.0kV | 3 sec | No instantaneous breakdown |
(3) Mechanical property test
Flexibility (bending test): bend around a mandrel of specified diameter to check for cracking.
Adhesion test: the glass fiber layer should not come loose (such as testing with tape stripping method).
Abrasion resistance (scratch test): scratch with a steel needle to check for insulation damage.
(4) Thermal performance test
Thermal Shock Test (e.g. 250℃/1h, no cracking).
Conditions:
Conductor temperature 250℃ maintained for 1 hour
Quick cooling to room temperature
Qualification standard:
No cracking or delamination of the insulation layer
The breakdown voltage does not drop by more than 20%
Long-Term Heat Aging (e.g. 155℃/1000h, performance does not drop by more than 50%).
Purpose: To evaluate the long-term high-temperature aging characteristics of the material
Method:
The sample is continuously aged at a set temperature (e.g. 155℃, 180℃), and the breakdown voltage and mechanical properties are tested regularly
Requirements:
After aging, the initial breakdown voltage must be maintained at more than 50%:
Grade 155: 5000 hours
Grade 180: 3000 hours
Softening breakdown test (to test the stability of the paint film at high temperatures).
Typical thermal performance test data
| Test Parameter | Class 155 (F) | Class 180 (H) |
| Continuous Operating Temp | 155°C | 180°C |
| Short-Term Overload | 200°C for 72h | 220°C for 48h |
| Heat Shock Resistance | Pass at 250°C | Pass at 280°C |
| Thermal Cycling | Pass 100 cycles | Pass 100 cycles |
| Temperature Index (TI) | ≥155 | ≥180 |
(5) Chemical resistance test
Solvent resistance (e.g. impregnation varnish is not soluble in transformer oil or coolant).
Moisture and heat resistance (85℃/85% RH, insulation resistance meets the standard after 48h).