• Inputs: Temperature sensors, smoke/gas detectors, magnetic door/window contacts, motion sensors, and pushbuttons (Start, Stop, Acknowledge/Reset).
• Controller: A PLC unit (such as Siemens S7-300, Mitsubishi, or Allen-Bradley) that processes signal states against a programmed control sequence.
• Outputs: Sirens, horns, flashing warning lamps, annunciator panels, HMI/SCADA screens, or automatic safety relays.
Common Applications
• Industrial & Process Plants: Monitors tank levels, pressure limits, temperature spikes, and emergency stop conditions, logging events to an HMI or control room.
• Fire & Safety Systems: Detects smoke or heat, triggers buzzers, shuts down electrical power supplies, and opens emergency exit paths.