The **FRTS-4Z-R** is an industrial-grade **Four-Zone Fire Alarm Control Panel** (Conventional). It is designed to monitor and manage fire detection sensors and notification appliances in small to medium-sized buildings. --- ### 1. Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Detection Zones** | 4 Independent Zones | | **Input Voltage** | 220V/230V AC (50/60Hz) | | **Operating Voltage** | 24V DC | | **Battery Backup** | Supports 2x 12V Lead-Acid Batteries | | **Alarm Outputs** | 2 Notification Appliance Circuits (NAC) | | **Auxiliary Power** | 24V DC for external modules | --- ### 2. Main Electronic Components and Modules The internal architecture of the FRTS-4Z-R consists of several critical electronic sections: #### A. Power Supply Unit (PSU) This section converts high-voltage AC utility power into stabilized 24V DC. It includes: * **Step-down Transformer:** Reduces mains voltage. * **Rectifier/Regulator Circuit:** Converts AC to DC and ensures a steady voltage to prevent damage to sensitive sensors. * **Charger Circuit:** Automatically maintains the backup batteries and switches to battery power instantly during a blackout. #### B. Zone Monitoring Circuitry The panel has 4 input circuits. Each zone uses **End-of-Line (EOL) Resistors** (typically 4.7kΩ or 6.8kΩ). * **Monitoring Logic:** The board constantly measures current flow. * *Normal:* Stable current. * *Open Circuit:* Zero current (indicates a broken wire). * *Short Circuit/Alarm:* High current (indicates a triggered smoke detector or pull station). #### C. Microcontroller Unit (MCU) The "brain" of the panel. It processes signals from the zones, manages the timing for fire drills, and controls the LED status indicators on the front interface. #### D. Output Relays * **Fire Relay:** A dry contact relay that triggers when a fire is confirmed. This can be used to shut down HVAC systems or recall elevators. * **Fault Relay:** Activates if there is a system malfunction (e.g., battery disconnected or wire cut). --- ### 3. Connection Interface The terminal block inside the unit typically follows this layout: | Terminal Label | Function | | :--- | :--- | | **L / N / E** | AC Mains Input (Live, Neutral, Earth) | | **Zone 1-4 (+/-)** | Connections for Smoke/Heat Detectors | | **Sounder (+/-)** | Connections for Sirens, Bells, or Strobes | | **Aux 24V** | Constant power for PIR sensors or beam detectors | | **Relay (NC/COM/NO)** | Voltage-free contacts for external integration | --- ### 4. Visual and Audible Indicators * **LEDs:** Green (Power), Red (Fire/Alarm), Amber (Fault/Trouble/Silence). * **Internal Buzzer:** Provides an immediate audible alert at the panel when a fault or fire is detected.