Learn About the Wiring Rules for Cable Trays!

2025-11-24 01:14:38

With the development of the times, cable trays are widely used, but we believe many people are not familiar with their wiring rules. Next, our company will introduce them to you!

Basic Wiring Rules

When cable trays are used for indoor wiring, cables shall not have jute or other flammable materials as outer sheaths.

For horizontal installation of Stainless Steel Cable Trays, the appropriate span shall be selected according to the support load curve, generally 1.5 ~ 3m. For vertical installation, the distance between fixed points shall not exceed 2m.

When cable trays are used for wiring in corrosive or particularly humid environments, corresponding protective measures shall be taken according to different corrosive media, and plastic-sheathed cables shall be appropriately selected.

When several groups of cable trays are installed in parallel at the same height, the maintenance and inspection distance between adjacent cable trays shall be considered.

Cables can be laid on cable trays without spacing. The cable filling rate of the tray cross-section:

Power cables: No more than 40%

Control cables: No more than 50%

The general horizontal installation height of cable trays (trays) shall not be less than 2.50 meters. For the part of vertical installation less than 1.80 meters above the ground, metal covers shall be added for protection, except when laid in electrical dedicated rooms (such as power distribution rooms, electrical shafts, technical floors, etc.).

Cable trays shall not be installed above corrosive gas pipelines and thermal pipelines, or below corrosive liquid pipelines. Otherwise, anti-corrosion and heat insulation measures shall be taken.

Special Wiring Rules

Cables of different voltages and uses shall not be laid on the same layer of the tray:

Cables for emergency lighting and other lighting purposes.

Cables above 1kV and below 1kV.

Bidirectional power cables used to supply power to main loads in the same path.

Power and weak current cables. If they need to be installed on the same layer of the tray due to special circumstances, they shall be separated by a partition.

When cable trays are parallel or cross with various pipelines, the net distance shall comply with the provisions of Table DQ4-1.

When cable trays pass through firewalls and fireproof floors, fire isolation measures shall be taken.

Cables in cable trays shall be marked with number, model, start and end points, etc., at the head end, tail end, turning points, and every 50m.

Cables in cable trays shall be fixed at the following positions:

For vertical laying: At the upper end of the cable and every 1.50 ~ 2m.

For horizontal laying: At the head and tail ends, turning points, and every 5 ~ 10m of the cable.