Arc-shielding plates must be installed by qualified personnel following manufacturer instructions, ensuring proper alignment, secure fastening, and compliance with clearance and safety standards.

Safety First

Before beginning installation, de-energize the distribution box and verify zero voltage. Only qualified electrical personnel should perform the work, using appropriate PPE such as arc-rated gloves, face shields, and protective clothing in accordance with NFPA 70E and OSHA regulations . Never attempt installation while the panel is energized.

Preparation

1. Review Manufacturer Documentation: Obtain the installation manual and customer drawing package for your specific distribution box or switchgear model .
2. Inspect Components: Ensure all arc-shielding plates, fasteners, and hardware kits are present and undamaged.
3. Check Clearances: Maintain minimum electrical clearances between live parts and the shielding plates as specified in the manual to preserve dielectric withstand capability .

Installation Steps

1. Position the Plates: Align the arc-shielding plates in the designated compartments, typically between busbars, incomers, and outgoing functional units. Ensure the plates cover potential arcing paths without obstructing normal operation.
2. Secure Hardware: Use the provided bolts, flat washers, split-lock washers, and nuts. Insert bolts through tie holes, loosely assemble all plates first, then torque hardware to manufacturer specifications once all plates are in place .
3. Verify Alignment: Ensure plates are flush and properly seated. Check for any gaps or misalignment that could compromise arc containment.
4. Insulate Connections: After installation, insulate all connections to live parts as recommended, using field taping procedures or insulating boots .

Final Checks

• Confirm that all plates are mechanically stable and cannot shift during operation.
• Verify that minimum phase-to-phase and phase-to-ground clearances are maintained.
• Ensure that the panel doors and covers close properly without interference from the plates.
• Conduct any required internal arc containment testing or visual inspection as per IEC TR 61641 or manufacturer guidance .

Maintenance Considerations

• Periodically inspect arc-shielding plates for damage, corrosion, or loosening.
• Replace any compromised plates immediately to maintain arc flash protection.
• Document installation and maintenance activities for compliance and safety audits. By following these steps, arc-shielding plates will provide effective internal arc containment, reducing the risk of injury and equipment damage during an arc flash event .