FDL Insulation-Piercing Lightning Protection Grounding Ring
The FDL insulation-piercing lightning protection grounding ring is designed to create an accessible grounding and voltage-testing point on covered overhead conductors. It combines a bolted insulation-piercing clamp with a red insulated U-shaped conductive loop.
When the clamp bolts are tightened to the specified torque, the conductive piercing elements penetrate the cable insulation and establish electrical contact with the conductor. The insulated loop provides a clearly identifiable operating point for temporary grounding equipment, voltage detectors and compatible lightning-protection arrangements.
The piercing structure normally allows installation without stripping the main conductor insulation, helping reduce installation time and limiting unnecessary damage to the cable covering. The exact conductor range, insulation thickness and tightening torque must match the selected product model.
Important: This product is a grounding and voltage-testing connection fitting. It is not a surge arrester and does not independently discharge lightning surges to earth. Its function and installation position must follow the approved overhead-line protection design.
Key Features
- Insulation-piercing connection for covered overhead conductors
- Normally installed without stripping the main cable insulation
- Red insulated loop provides clear visual identification
- Exposed metal contact section for compatible operating tools
- Bolted clamp construction provides controlled contact pressure
- Suitable for voltage testing and temporary grounding operations
- Can be incorporated into compatible distribution-line lightning-protection arrangements
- Conductor range, loop size and hardware configuration can be customized
Typical Technical Specifications
| Product Series | FDL |
|---|---|
| Product Type | Insulation-Piercing Lightning Protection Grounding Ring |
| Connector Type | Bolted insulation-piercing clamp |
| Conductor Type | Covered overhead conductor / aerial insulated conductor |
| Voltage Class | Distribution voltage; selected according to the product model |
| Conductor Range | According to conductor cross-section, outer diameter and insulation thickness |
| Loop Shape | U-shaped grounding loop |
| Loop Construction | Conductive metal loop with weather-resistant polymer insulation |
| Insulation Color | Red |
| Clamp Body | Aluminum alloy, subject to model confirmation |
| Piercing Components | Conductive metal piercing inserts, subject to model confirmation |
| Fasteners | Galvanized steel or stainless steel according to the order specification |
| Installation Method | Bolt tightening to the specified installation torque |
| Applications | Voltage testing, temporary grounding and lightning-protection coordination |
| Customization | Conductor range, loop dimensions, insulation color, hardware and packaging |
Specifications must be confirmed using the approved drawing and test report for the exact FDL model. The product photograph alone cannot establish its voltage rating, conductor range or short-circuit current capacity.
Working Principle
The clamp is positioned over the covered conductor and tightened evenly. As the bolts are tightened, the piercing elements penetrate the polymer covering and contact the conductor. The resulting electrical path connects the conductor to the metal grounding loop.
The red polymer covering insulates most of the loop and improves visibility. The designated exposed metal section is used as the contact point for an approved voltage detector, temporary grounding clamp or compatible protection component.
Applications
- Covered overhead distribution conductors
- 10 kV aerial insulated cable systems when matched to an approved model
- Temporary grounding connection points
- Voltage-testing points for line maintenance
- Overhead-line lightning-protection coordination
- Distribution-line inspection and maintenance systems
- Utility grid construction and renovation projects
Installation Guidance
- Confirm the conductor material, cross-section, outer diameter and insulation thickness.
- Select an FDL model compatible with the conductor and system voltage.
- Inspect the clamp, piercing components, loop insulation and fasteners before installation.
- Position the clamp at the location specified on the approved line drawing.
- Keep the conductor centered inside the piercing clamp.
- Tighten the bolts evenly using the specified sequence and torque.
- Do not reuse a piercing connector unless the manufacturer specifically permits reuse.
- Verify the orientation and accessibility of the exposed grounding contact.
- Inspect the assembly for loose hardware, damaged insulation or abnormal deformation.
Installation should normally be carried out on a de-energized and properly grounded line. Live-line installation is permitted only when an approved utility procedure, suitable tools and qualified personnel are available.
Inspection and Testing
- Dimensional and visual inspection
- Clamp-body and fastener inspection
- Piercing-contact resistance test
- Temperature-rise test where specified
- Mechanical holding or pull-out test
- Short-circuit current withstand test where required
- Power-frequency and impulse-voltage testing for the complete application
- Polymer insulation weathering and tracking-resistance evaluation
- Packaging, marking and quantity inspection
Reference Standards
- GB/T 2314-2008 – General technical requirements for electric power fittings
- GB/T 14049-2008 – Aerial insulated cables for rated voltage of 10 kV, when applicable
- IEC 61284:1997 – Requirements and tests for overhead line fittings, where contractually applicable
- Applicable utility standards, project drawings and local electrical regulations
Reference to a standard does not constitute certification. Compliance must be demonstrated through valid inspection or test documentation for the exact product model.
Ordering Information
Please provide the following information when requesting a quotation:
- System rated voltage
- Conductor material and construction
- Conductor cross-sectional area
- Cable outer diameter and insulation thickness
- Required grounding-loop dimensions
- Required short-circuit current and duration
- Clamp-body and hardware material requirements
- Installation torque or shear-head requirement
- Applicable standard and required test reports
- Order quantity, marking and packaging requirements
Frequently Asked Questions
Is this product a lightning arrester?
No. It is a grounding and voltage-testing connection fitting. It may form part of a lightning-protection arrangement, but it does not replace a surge arrester.
Does the conductor insulation need to be removed?
A correctly selected insulation-piercing model normally establishes contact without stripping the main conductor insulation. Installation must follow the manufacturer’s instructions.
Can it be used as a temporary grounding point?
Yes, provided that the exact product model, exposed contact dimensions and current-withstand capacity are approved for the grounding equipment and operating procedure.
Can it be installed on an energized line?
Only qualified personnel using an approved live-line procedure and suitable insulated tools may perform energized installation. Otherwise, the circuit must be de-energized and secured before installation.
Does the red insulated section serve as the electrical contact?
No. The red covering is an insulating and identification layer. Electrical contact must be made at the designated exposed metal section.
