The **KAC-ABC-R/Q** refers to a series of electronic modules specifically used in **Addressable Fire Alarm Systems**, typically manufactured by KAC Alarm Company (a subsidiary of Honeywell). These are commonly used as interface modules to bridge conventional devices or auxiliary equipment into an addressable loop. --- ## 1. Core Technical Specifications The "R/Q" suffix usually denotes specific mounting or functional variants (such as Relay output or Monitored Input). | Feature | Specification Details | | :--- | :--- | | **Communication Protocol** | Proprietary Addressable Loop (e.g., Morley-IAS, System Sensor) | | **Operating Voltage** | 15V - 32V DC (Loop powered) | | **Standby Current** | ~300μA - 500μA | | **Addressing Method** | Rotary Switches (01-99 or 01-159) | | **Terminal Connections** | Screw terminals (0.5mm² to 2.5mm²) | | **Operating Temperature** | -20°C to +60°C | --- ## 2. Key Electronic Components The internal PCB of these modules consists of several critical stages to ensure safety and reliability: ### A. The Microprocessor & ASIC The heart of the module is an Application Specific Integrated Circuit (ASIC) or a low-power microcontroller. This chip handles: * **Decoding:** Interpreting the polling data from the Fire Alarm Control Panel (FACP). * **Addressing:** Reading the physical position of the rotary switches. ### B. Loop Isolation (Optional) Many "R/Q" variants include a built-in **Short Circuit Isolator**. * **Function:** If a short circuit occurs on the loop, the electronic switch opens to prevent the entire loop from failing. * **Component:** High-speed MOSFETs triggered by overcurrent sensing circuitry. ### C. Input/Output Interfacing * **Relay (R variant):** Contains a latching or non-latching electromechanical relay. This allows the system to trigger external hardware like door magnetic holders or fire shutters. * **Monitoring Circuit (Q/Input variant):** Uses an End-of-Line (EOL) resistor to monitor for "Open Circuit" or "Short Circuit" conditions on the external wiring. --- ## 3. Physical Layout and Wiring The module is typically housed in a plastic enclosure designed for DIN-rail mounting or surface boxes. ```markdown Terminal Block Layout (Typical): 1. Loop In (+) 2. Loop In (-) 3. Loop Out (+) 4. Loop Out (-) 5. Relay Contact / Input (+) 6. Relay Contact / Input (-) ``` --- ## 4. Addressing Logic The module uses two **Rotary Decadic Switches** to set the address. * **TENS Switch:** Sets the first digit (0-15). * **UNITS Switch:** Sets the second digit (0-9). * *Example:* Setting TENS to '4' and UNITS to '2' assigns the device Address 42. ---