The **AH-24WP-R** is an outdoor-rated, weather-proof audible notification appliance, commonly manufactured by Potter Electric Signal Company. It is primarily used in fire alarm and emergency signaling systems. --- ### Technical Specifications & Electronic Components The device is engineered to operate in harsh environmental conditions while maintaining consistent sound output. | Component | Specification | | :--- | :--- | | **Input Voltage** | 24V DC or FWR (Full Wave Rectified) | | **Operating Range** | 16V to 33V DC | | **Current Draw** | Ranges from 24mA to 74mA (depending on tone/volume) | | **Sound Output** | Up to 90-95 dBA at 10 feet | | **Ingress Protection** | NEMA 4X / IP56 Rated (Weatherproof) | | **Mounting** | Surface mount with BBX-4 backbox | --- ### Key Electronic Features #### 1. Internal Tone Generator The unit contains an integrated circuit (IC) that generates various selectable tones. Unlike old mechanical bells, this is a **solid-state electronic device**. * **Temporal 3 Tone:** The standard interrupted pattern for fire evacuation. * **Continuous Tone:** A steady horn output. * **March Time:** A repetitive rhythmic pulse. #### 2. Polarized Circuitry The device features an internal diode for **electrical supervision**. * In a standby state, the Fire Alarm Control Panel (FACP) reverses polarity to check for wire integrity. * The diode ensures that the horn only activates when the polarity is switched to the active state. #### 3. Terminal Block & Wiring The AH-24WP-R utilizes a plug-in terminal block design. This allows for: * **In-Out Wiring:** Two terminals for positive and two for negative, ensuring the circuit is supervised (if a device is removed, the panel detects an open circuit). * **Gauge Support:** Typically supports 12 to 18 AWG wire. #### 4. Weatherproofing (The "WP" Suffix) Electronic components are protected by: * **Conformal Coating:** A thin chemical layer applied to the internal PCB to protect against moisture, dust, and corrosion. * **Gasketed Housing:** A silicone or rubber gasket seals the electronics within the red plastic (R) housing. --- ### Comparison of Operational Modes | Tone Selection | Frequency | Application | | :--- | :--- | :--- | | **Temporal** | 2400Hz (approx) | Standard Fire Evacuation | | **Steady** | Constant | General Alert / Mass Notification | | **Whoop** | Ascending | High-noise environments |