Temperature-sensing cables, such as linear heat detection (LHD) cables, should be installed along the full length of cable trays, positioned to detect hot spots early, and mounted securely using clips or protective sleeves to ensure reliable monitoring.

Key Considerations

Purpose: Temperature-sensing cables are used to detect overheating or fire hazards in cable trays, which can occur due to overloaded cables, loose connections, or insufficient heat dissipation. Early detection prevents fire spread and operational downtime . Cable Type: Linear heat detection cables or fiber optic distributed temperature sensing systems are commonly used. Fiber optic cables are EMI-resistant and suitable for long distances, while LHD cables provide preset or programmable temperature detection .

Installation Guidelines

Positioning:

• For trays up to 0.6 m (2 ft) wide, a single run of cable should be centered above the tray .
• For trays wider than 0.6 m, two runs should be spaced evenly across the tray width .
• In multi-tier trays, cables can be mounted above or below each tier using V-clips, L-clips, or beam clips .
• Maintain a height of 150–250 mm above the tray surface to avoid obstruction by power or data cables . Mounting and Protection:
• Use appropriate clips to secure the cable and prevent sagging or accidental dislodging .
• Protective silicone sleeves or stainless steel braided coatings are recommended to prevent abrasion from tight zip ties or environmental exposure .
• Avoid painting or covering the detection cable, as this can impair its thermal response . Environmental Considerations:
• Ensure the cable is resistant to dust, moisture, vibration, and temperature fluctuations common in industrial or infrastructure settings .
• For areas with electrical surges or EMI, choose EMI-resistant cables to prevent false alarms . Integration and Maintenance:
• Connect the sensing cable to a supervised fire alarm or monitoring system for real-time alerts .
• Regularly inspect and maintain the cable, especially when adding or removing power cables, to prevent tangling or damage .

Summary

Proper installation of temperature-sensing cables involves strategic positioning, secure mounting, environmental protection, and integration with monitoring systems. Following these guidelines ensures early detection of overheating, reduces fire risk, and maintains operational continuity in cable tray networks .