Cable tray installation for linear temperature-sensitive cables

Linear heat detection cables should be installed centrally or evenly spaced in cable trays, using appropriate clips and protective measures to ensure accurate temperature monitoring and prevent physical damage.

Placement and Spacing

For single-tier cable trays up to 0.6 meters (2 feet) wide, a single run of linear heat detection (LHD) cable should be positioned in the center of the tray. For wider trays, use two runs spaced evenly across the tray width to ensure full coverage and early detection of temperature anomalies . The cable should be 150–250 mm above the tray or suspended just below using suitable clips, avoiding obstruction of power or data cables .

Mounting Methods

• V-Clips, L-Clips, or beam clips are recommended for securing cables above or below trays, including multi-tier configurations .
• Protective silicone sleeves or stainless steel braided cables are advised to prevent abrasion from tight zip ties or contact with other cables .
• Ensure proper sag in the cable to avoid tension that could damage the inner core or thermal sheathing .

Multi-Tier and High-Risk Areas

• For multi-tier trays, cables can be mounted underneath the tray to monitor each level effectively .
• In high-risk zones (e.g., near roller bearings or high-energy cable bundles), additional runs of LHD cable may be installed to detect localized overheating early .

Environmental Considerations

• Cable trays often experience dust, humidity, vibration, and temperature fluctuations, which can interfere with conventional sensors. Linear heat detection cables are designed to operate reliably under these conditions .
• Avoid painting or covering the detection cable, as this can impair its thermal response .
• Splices should be wrapped with splicing tape to prevent moisture ingress, and low-temperature splicing tape should be used if installation occurs below 0°C .

Compliance and Standards

Linear heat detection systems for cable trays are typically certified to EN54-28, UL, VdS, CE, and RoHS, ensuring compliance with global fire safety standards . Proper installation according to manufacturer guidelines ensures early detection of overheating and reduces the risk of fire propagation along cable routes .

Summary

To optimize temperature monitoring in cable trays:

1. Center or evenly space LHD cables depending on tray width.
2. Use appropriate clips and protective sleeves to secure cables.
3. Maintain proper sag and avoid obstruction of other cables.
4. Consider multi-tier and high-risk areas for additional coverage.
5. Follow environmental and splicing precautions to maintain cable integrity.
6. Ensure compliance with relevant fire safety standards for reliable operation. This approach ensures early detection of overheating, protects sensitive cables, and maintains the integrity of the fire detection system.