What is used to protect a wire bundle from chafing where it passes through a bulkhead or frame hole?

What is used to protect a wire bundle from chafing where it passes through a bulkhead or frame hole?

• A. A grommet around the edges
• B. Electrical tape wrap
• C. Heat-shrink alone
• D. A metal clip

Answer: (A)

When a wire bundle passes through a bulkhead or frame hole, the edge of the hole can be sharp and the bundle can rub against it as the aircraft vibrates. A grommet around the edge provides a smooth, cushioned surface that shields the insulation from abrasion. It distributes any contact pressure evenly and protects the wires from chafing, which helps prevent insulation damage and potential electrical faults. Electrical tape wrap isn’t reliable for edge protection; it can wear away, slip, or bunch up. Heat-shrink alone doesn’t address the rough edge and won’t shield the bundle from the sharp edge of the hole. A metal clip may hold or route the bundle but offers no cushioning to prevent chafing. That cushioning and edge protection is provided most effectively by a grommet.

When a wire bundle passes through a bulkhead or frame hole, the edge of the hole can be sharp and the bundle can rub against it as the aircraft vibrates. A grommet around the edge provides a smooth, cushioned surface that shields the insulation from abrasion. It distributes any contact pressure evenly and protects the wires from chafing, which helps prevent insulation damage and potential electrical faults.

Electrical tape wrap isn’t reliable for edge protection; it can wear away, slip, or bunch up. Heat-shrink alone doesn’t address the rough edge and won’t shield the bundle from the sharp edge of the hole. A metal clip may hold or route the bundle but offers no cushioning to prevent chafing. That cushioning and edge protection is provided most effectively by a grommet.