Standard cable tray tees, including left upper tees, are sized to match the nominal width and depth of the main and branch trays, typically ranging from 100 mm to 600 mm in width and 50 mm to 150 mm in depth.

Standard Dimensions

Width and Depth: The width of a cable tray tee is generally the same as the main run to ensure seamless cable transition and structural compatibility. Common nominal widths include 100 mm, 150 mm, 200 mm, 300 mm, 400 mm, 500 mm, and 600 mm, while standard depths (side rail height) range from 50 mm to 150 mm depending on cable fill requirements and heat dissipation needs . Branch Tee Orientation: A left upper tee is a horizontal fitting that branches off to the left at a 90° angle from the main tray. The branch width and depth usually match the main tray, but in some cases, a reducer may be used if the branch requires a smaller capacity . Material Thickness: Standard material thickness for steel or aluminum trays ranges from 1.2 mm to 2.5 mm for light to medium duty, and up to 3 mm for heavy-duty applications. This ensures structural integrity and compliance with load ratings . Length and Radius: The tee fitting length is typically 300 mm to 600 mm along the branch to allow proper cable bending and installation. The bend radius at the junction is designed to prevent cable damage, often following a minimum radius of 1.5 times the tray width for power cables . Standards Compliance: Cable tray tees, including left upper tees, are manufactured according to IEC 61537, NEMA VE 1, and UL 568 standards to ensure compatibility, safety, and load-bearing capacity .

Practical Considerations

• Ensure the tee width matches the main tray to avoid overcrowding or cable congestion.
• Verify the depth is sufficient for the total cable fill, considering NEC fill tables.
• Use splice plates and hardware supplied with the fitting to maintain structural integrity.
• For installations in tight spaces, check the outside dimensions including side rail thickness to ensure clearance . By following these standard dimensions and guidelines, a left upper cable tray tee can be selected to provide code-compliant, structurally sound, and future-ready cable routing.