How can we improve the safety of maintenance personnel through the development of insulated temporary grounding clamps?

 

During maintenance activities on electrical assets, electricians use temporary grounding clamps to ensure operational safety. AXIA Energia has identified an opportunity to enhance the design of temporary grounding clamps used for connections to grounding grids and grounded structures by incorporating integrated insulation into the conductive components.

This improvement aims to increase the level of insulation that protects electricians in the event of an incorrect installation or removal sequence of Temporary Grounding (AET) assemblies, reducing exposure to electrical hazards and improving overall safety during maintenance operations.

Impact of the Solution on Maintenance Activities

The proposed solution should develop an insulated temporary grounding clamp for use in transmission lines, substations, and power plants, with the following objectives:

• Implement an insulation level capable of protecting electricians from contact with live conductive parts subjected to induced voltage.
• Improve the functionality and reliability of temporary grounding clamps.
• Reduce risk exposure by protecting technicians even in cases of procedural errors or accidental drops of grounding cables during switching operations.

Technical Requirements
 

• Materials with Adequate Dielectric Properties: Use high-dielectric-strength insulating materials capable of withstanding induced voltages in extra-high-voltage transmission systems. The insulation level must be equal to or greater than that provided by a 17 kV insulating glove.
• Resistance to Adverse Environmental Conditions: The insulation system must withstand temperature variations, humidity, vibration, UV radiation, and chemical agents, ensuring durability and reliable performance in harsh outdoor environments.
• Ergonomics and Handling: The insulated design must allow efficient operation, be adapted to the human hand, and prevent accidental contact between any part of the hand and points that may become energized.
• Installation and Operation: The insulation must allow electricians to inspect the connection between the cable and the clamp without requiring special tools or complex procedures. It should include an accessible inspection area that can be safely opened and closed.
• Locking Mechanism: Develop a locking system that prevents the clamp connected to the grounding side from being removed while the phase-side clamp remains connected.

Recommended Testing and Validation

To ensure the effectiveness and safety of the developed insulation system, the following tests are recommended:

Dielectric Strength Test

Objective: Verify the ability of the insulating material to withstand electrical stress without dielectric breakdown.

Procedure: Apply progressively increasing voltage until dielectric breakdown occurs or the specified test voltage is reached, in accordance with applicable technical standards.

Reference: Standards that define requirements for tools used in live-line maintenance, including dielectric and mechanical testing to ensure the tools can withstand both electrical and mechanical stresses.

Note: As a project deliverable, the recommended frequency for dielectric strength testing to be performed by AXIA Energia maintenance teams should be established.

Insulation Resistance Test

Objective: Measure the electrical resistance of the insulating material to ensure that leakage currents do not compromise safety.

Procedure: Apply DC voltage between conductive components and insulated surfaces, measure leakage current, and calculate insulation resistance.

Reference: Standards defining withstand-voltage testing, dielectric strength, insulation resistance, and mechanical tests for equipment used in live-line maintenance activities.

Accelerated Aging Test

Objective: Evaluate the durability of the insulating material under extreme environmental conditions, simulating long-term aging.

Procedure: Expose the material to cycles of temperature, humidity, vibration, and UV radiation in accordance with applicable standards to assess changes in dielectric and mechanical properties.

Reference: Standards establishing requirements for materials used in live-line maintenance equipment, including resistance to adverse environmental conditions.

Mechanical Strength Test

Objective: Ensure that the insulation system does not compromise the structural integrity of the clamp during installation, removal, and accidental impact or drop events.

Procedure: Apply mechanical loads representative of field conditions and evaluate tensile, compression, and impact resistance.

Reference: Standards establishing dielectric and mechanical performance requirements for tools used in live-line maintenance.

Personal Protective Equipment (PPE) Compatibility Test

Objective: Verify that the new insulation system allows the use of insulating gloves without compromising worker safety.

Procedure: Conduct practical tests using different classes of insulating gloves to assess the effectiveness of the insulated clamp when used together with PPE.

Submission Deadline

The proposal submission form will remain available until August 22, 2025.

Questions

For questions or additional information, please send an email and include the title of this Challenge in the subject line to innovationgrid@axia.com.br.

 

 

 

Temporary Grounding | Grounding Clamps | Asset Maintenance | Occupational Safety | Electrical Insulation