EX-3 Spool Insulator — IEC Standard Brown or Light Gray Porcelain Insulator
The EX-3 spool insulator is a porcelain insulator manufactured in compliance with IEC Standard requirements for overhead line insulators. It is available with a brown or light gray glaze finish, providing flexibility for different aesthetic and environmental requirements.
Also known as a shackle insulator, this spool-type insulator is designed for low-voltage distribution lines, providing reliable insulation and conductor support at line terminals, tension poles, and corner poles. The EX-3 model features a compact cylindrical body with circumferential wire grooves that secure conductors via soft-bending tie wires. It can be mounted in either vertical or horizontal positions, making it versatile for various pole-top configurations.
With a diameter of 65 mm and a height of 65 mm, the EX-3 is a compact and lightweight spool insulator, ideal for applications where space and weight are critical. Its net weight is approximately 0.35 kg per unit.
EX-3 Spool Insulator Technical Specifications
| Parameter | Value |
| Model | EX-3 |
| Product Type | Spool / Shackle Insulator |
| Material | Porcelain |
| Glaze Color | Brown or Light Gray |
| Compliance | IEC Standard |
| Diameter (D) | 65 mm |
| Height (H) | 65 mm |
| Transverse Strength | 9.1 kN |
| Low Frequency Dry Flashover Voltage | 20 kV |
| Low Frequency Wet Flashover Voltage, Vertical | 8 kV |
| Low Frequency Wet Flashover Voltage, Horizontal | 10 kV |
| Net Weight, Approximate | 0.35 kg |
Dimensions and Design
The EX-3 spool insulator has a diameter of 65 mm and a height of 65 mm. The compact design allows for efficient stacking and transportation, with a net weight of approximately 0.35 kg per unit. The brown or light gray glaze finish provides enhanced weathering resistance and UV stability for outdoor overhead line applications.
Mechanical Performance
With a transverse strength of 9.1 kN, the EX-3 spool insulator is engineered to withstand the mechanical loads encountered in low-voltage distribution networks, including conductor tension at terminal poles and sharp turns. This mechanical rating ensures reliable performance under continuous tensile stress.
Electrical Characteristics
The EX-3 insulator delivers dependable electrical insulation performance:
- Low Frequency Dry Flashover Voltage: 20 kV
- Low Frequency Wet Flashover Voltage, Vertical: 8 kV
- Low Frequency Wet Flashover Voltage, Horizontal: 10 kV
These ratings confirm the insulator’s suitability for low-voltage overhead distribution systems. The wet flashover performance in both vertical and horizontal mounting orientations provides design flexibility for utility engineers.
EX-3 Spool Insulator Standards and Compliance
The EX-3 spool insulator is manufactured to comply with IEC Standard requirements for overhead line insulators. IEC standards are published by the International Electrotechnical Commission (IEC). Relevant standards and publications can be found through the IEC Webstore.
For related industry references, see also ANSI and British Standards Institution (BSI)
.
Applications
The EX-3 spool insulator is primarily used in low-voltage overhead distribution lines for:
- Terminal poles — supporting conductors at the end of distribution runs
- Tension poles — managing mechanical loads at line angles
- Corner poles — providing insulation at sharp direction changes
- Secondary racks — dead-ending or supporting secondary voltage conductors
Spool insulators are mounted either vertically or horizontally and are secured using spool bolts, clevises, or secondary racks. The conductor is tied into the circumferential grooves using soft-bending wire, ensuring a secure and insulated connection.
Installation Notes
- The insulator is mounted axially, with loading applied to the circumferential grooves.
- Conductors are secured in the grooves using soft-bending tie wires.
- The insulator can be bolted to the cross-arm of the pole.
- Both vertical and horizontal mounting positions are supported.
Packing and Shipping
| Parameter | Value |
| Net Weight, Approximate | 0.35 kg |
| Glaze Color | Brown or Light Gray |
| Material | Porcelain |
The compact size and lightweight design make the EX-3 spool insulator cost-effective to transport and install. Standard export packaging is available, and customization options may be offered by manufacturers upon request.
Related Products
Explore related insulator product lines:
- EX-3 Spool Insulator
- EX-2 Spool Insulator
- 1617 Spool Insulator
- ED-2B Shackle Insulator
- ED-2B1 Shackle Insulator
- ED-2C Shackle Insulator
- ANSI 53-1 Spool Insulator
- ANSI 54-3 Porcelain Stay Insulator
- Spool Insulators Category
- Shackle Insulators Category
Frequently Asked Questions
Q: What standard does the EX-3 spool insulator comply with?
A: The EX-3 spool insulator complies with IEC Standard requirements for overhead line insulators.
Q: What glaze colors are available for the EX-3?
A: The EX-3 is available with brown or light gray glaze.
Q: Can the EX-3 insulator be mounted horizontally?
A: Yes. The EX-3 spool insulator supports both vertical and horizontal mounting, with wet flashover voltages of 8 kV vertical and 10 kV horizontal.
Q: What is the transverse strength of the EX-3 insulator?
A: The transverse strength is 9.1 kN, suitable for low-voltage distribution line applications.
Q: What is the net weight of the EX-3 spool insulator?
A: The approximate net weight is 0.35 kg per unit.
Q: What material is used for the EX-3 spool insulator?
A: The EX-3 is manufactured from porcelain with a brown or light gray glaze finish for outdoor durability.
Contact and Customization
For inquiries regarding the EX-3 spool insulator — including pricing, samples, bulk orders, or OEM customization — please contact our sales team. We offer factory-direct pricing, timely delivery, and customer-specific design services for utility and distribution projects.
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