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Project Overview: We are designing a critical-infrastructure residential fire suppression system (misters & sprinklers) that must operate reliably during wildfire events. The system manages dual water sources (City vs. Pool), high-pressure pumps, and multi-zone prioritization logic. The Core Challenge: We prefer an Industrial PLC (Allen-Bradley Micro850 or Siemens LOGO!) for maximum fail-safe reliability. However, the system must receive "Wake Up" triggers from modern cloud sources (Watch Duty API, Home Assistant, AI Cameras). We need you to design the "Bridge": How do we get a JSON/REST API alert into an industrial PLC that speaks Ladder Logic/Ethernet/IP, without compromising security or reliability? Hardware Preferences (In Order): Primary Choice: Allen-Bradley Micro850 (High density, no expanders preferred) or Siemens LOGO!. Secondary Choice: Controllino MEGA (Industrial Arduino) – Only if you can demonstrate it is as fail-safe as an AB unit. Scope of Work: Architecture Design: Propose the hardware interface between the Smart Home ecosystem (Home Assistant/Node-RED) and the Industrial PLC. (e.g., Dry contacts? Modbus TCP? MQTT Gateway?). Logic Programming: Fail-Over Logic: Monitor 4-20mA pressure sensors; if City Water less than 30 PSI, isolate city and switch to Pool Pump. Zoning Logic: Manage 3-Valve Bypass groups. Run Critical Zones (Eaves) continuously and Non-Critical Zones (Roof) on a timer cycle. Safety Loops: Hydraulic shock prevention (Cycle Stop Valve logic) and Pump Run-Dry protection. Documentation: Deliver a wiring schematic and fully commented code. Required Skills: Expertise in Allen-Bradley Connected Components Workbench (CCW) or Siemens Soft Comfort. Experience bridging Industrial Protocols (Modbus, Ethernet/IP) with IoT/Web Protocols (MQTT, REST, Webhooks). Experience with process control (pumps, valves, pressure transducers). To Apply, Please Answer the Following: The "API Bridge" Solution: If we use an Allen-Bradley Micro850, exactly how would you reliably get a "Fire Alert" signal from a web source (like Watch Duty) into the PLC? (Hardware relay? Middleware like Node-RED? Modbus?) Hardware Recommendation: For a system with ~25 I/O points that needs to last 15 years, would you stick with the Micro850 or recommend a different specific model? Experience: Briefly describe one project where you integrated a PLC with a non-industrial external trigger.