How to get vertical cable trays into cable wells

Vertical cable trays can be installed into cable wells using proper support brackets, riser clamps, and sealing methods to ensure structural integrity and watertightness.

Structural Support and Mounting

When installing cable trays vertically, it is essential to use appropriate brackets, hangers, or riser supports to secure the tray to the wall or well structure. Wire mesh baskets or perforated trays are often preferred for vertical runs due to their lighter weight and ventilation properties, which help prevent overheating of cables. Splice connectors should be used to maintain structural integrity, and cable ties alone are insufficient to support the load.

Vertical rail systems with hooks can also be used to hang cables, reducing the risk of over-tightening and insulation damage.

Securing Cables

Cables must be secured to every rung or support point to prevent sliding or piling, which can lead to heat buildup and reduced ampacity. Avoid turning horizontal trays on their side without proper vertical support, as this can compromise cable performance and future flexibility for additions. Ensure that the bent radii of cables are observed to prevent damage during vertical routing.

Watertight Penetrations

For cable wells that are exposed to water or buried, watertight sealing is critical. Options include using PVC conduit with rubber pipe sleeves, specialist sealing products like Roxtec or Hawke transit systems, or creating a dam around the cables and filling it with flowable silicone such as Dow Corning 734. Individual cable seals are recommended for achieving a truly watertight penetration, especially in challenging environments like coastal or underground installations.

Best Practices

Follow manufacturer specifications for weight limits and mounting hardware. Use multi-directional trays designed for both horizontal and vertical runs. Plan for future cable additions by maintaining proper spacing and support.

Consider thermal effects: vertical stacking can increase heat accumulation, so de-rating of cables may be necessary. Ensure compliance with standards such as DIN EN 61537 for cable support systems. By combining proper structural support, secure cable attachment, and effective sealing, vertical cable trays can be safely and efficiently routed into cable wells while maintaining performance and compliance.