Drilling holes for cable tray hanger installation

Drill holes according to manufacturer specifications, typically 7/16” for center hangers and 3/8” for clearance, ensuring proper alignment and secure attachment to structural supports.

General Guidelines

When installing cable tray hangers, it is crucial to follow the tray manufacturer's instructions and comply with local electrical codes such as the NEC or CEC . Supports must be strong enough to carry the tray load, and structural members should never be cut. Maintain at least 12 inches of clearance above and to the side of the tray for accessibility and future maintenance .

Hole Sizes and Placement

• Center Hanger Holes: Drill a 7/16-inch diameter hole in the solid bottom of the tray, typically 1 inch from the inside edge .
• Clearance Holes: For vertical or shelf brackets, drill 3/8-inch clearance holes to allow bolts to pass through without binding .
• Dropout or End Fittings: Use the tray or dropout as a template to mark 5/16-inch holes for mounting brackets . Ensure holes are aligned with the support points marked along the tray route, usually spaced every 1.5 to 2 meters depending on tray type and load .

Tools and Materials

• Drills: Power drill for metal, hammer drill for concrete supports.
• Anchors: Expansion bolts for concrete or drop-in anchors for ceiling suspension.
• Fasteners: Bolts, nuts, washers, and spring nuts as specified by the manufacturer .
• Safety Gear: Gloves, safety glasses, and hard hats are essential .

Installation Tips

1. Mark Support Points: Use a chalk line or laser level to ensure straight alignment.
2. Drill Holes: Drill at the marked points, ensuring proper diameter and depth.
3. Install Anchors: Insert wall or ceiling anchors before attaching brackets.
4. Attach Hangers: Secure the tray to the brackets using bolts and washers, ensuring the tray is level.
5. Check Load Capacity: Verify that each hanger can support the tray and cable weight, typically up to 318–340 kg per hanger for ladder trays . Following these steps ensures a safe, code-compliant, and durable cable tray installation while minimizing the risk of damage to cables or structural elements.