Complete List of Cable Tray Support Arm Size Specifications

Cable tray support arms are sized based on tray width, load requirements, and span, with standard dimensions ranging from 150 mm to 900 mm widths and adjustable arm lengths to ensure proper support.

Standard Cable Tray Support Arm Guidelines

Support arms are used to mount cable trays to walls, ceilings, or other structures, ensuring stability and load-bearing capacity. The sizing depends on the tray width, type, and expected cable load. Key parameters include: Tray Widths: Standard cable tray widths are 150 mm, 203 mm, 300 mm, 450 mm, 600 mm, 750 mm, and 900 mm.

Support Arm Length: Typically, the arm extends perpendicular from the mounting surface to the tray side rail. The length should match the tray width plus clearance for installation and cable bending. Rung Spacing: For ladder-type trays, standard rung spacing is 150 mm, 225 mm, or 300 mm; ventilated trays have a maximum opening of 52 mm.

Material: Support arms are usually made of steel or stainless steel, with galvanization or other corrosion-resistant finishes for durability. Load Considerations: The arm must support the tray and cable weight, including dynamic loads during installation. I-beam designs are preferred for higher strength, offering 15–20% more load capacity than C-shaped arms.

Example Specification Table

Tray Width (mm)Support Arm Length (mm)MaterialMax Load (kg)Notes150200–250Steel50–75Short span, light cables300350–400Steel100–150Standard span450500–550Stainless Steel150–200Medium span, heavier cables600650–700Stainless Steel200–250Long span, industrial use750800–850Steel250–300Heavy-duty applications900950–1000Steel300–350Maximum standard widthNotes: Arm length should allow for proper tray alignment and cable bending radius. Load ratings depend on tray type, cable weight, and span; consult manufacturer data for exact values. For spans exceeding standard lengths, additional intermediate supports are recommended.

Installation Considerations

Ensure support arms are level and securely anchored to the mounting surface. Use compatible fasteners and brackets as specified by the tray manufacturer. Verify compliance with BS EN 61537 or equivalent standards for cable support systems.

Consider environmental factors such as corrosion, temperature, and vibration when selecting material and finish. This table and guidelines provide a practical reference for selecting and installing cable tray support arms, ensuring structural integrity and compliance with industry standards.