They Help Fire Equipment Work Right The wires in cable trays connect to fire equipment like fire alarms, sprinkler systems, and gas fire put-out systems. These devices need to react quickly if a fire happens. They send alarms or start putting out the fire. Electrical lines can ignite themselves due to overheating or a short-circuit or they can be set alight by the external influence of fire or heat. The mostly combustible cable sheaths and. Cable tray installation must comply with specific technical standards to ensure electrical safety, system reliability, and long-term maintainability. Route. ProReact Linear Heat Detection (LHD) offers a proven solution. Engineered for continuous monitoring and early warning, our cable-based detection system is ideal for protecting cable trays—whether single-tier, multi-tier, or densely packed.