The part number **18AT-64-R/BL** refers to a specialized electromechanical component, typically identified as a **Toggle Switch Assembly** within the **Honeywell MICRO SWITCH™ AT Series**. These switches are engineered for high-reliability environments, such as aerospace, military, and heavy industrial applications. --- ## 1. Technical Specifications Below are the primary technical characteristics of the 18AT-64-R/BL: | Feature | Specification | | :--- | :--- | | **Manufacturer** | Honeywell (Sensing and Productivity Solutions) | | **Series** | AT Series (Toggle Switch) | | **Contact Configuration** | 4PDT (Four Pole, Double Throw) | | **Actuator Action** | 3-Position (Maintained - Maintained - Maintained) | | **Terminal Type** | Solder Terminals | | **Mounting Type** | Panel Mount (Bushings) | | **Construction** | Metal Toggle with Hermetic/Environmentally Sealed units | --- ## 2. Component Breakdown The assembly is modular, meaning it consists of several sub-components integrated into a single unit: * **Actuator (Toggle):** The "18AT" prefix indicates the physical housing style and toggle mechanism. It is designed for "fingertip" operation with a positive tactile feel. * **Basic Switches:** This assembly uses four individual **SM Series** subminiature switches ganged together. When the toggle is moved, it triggers all four switches simultaneously. * **Environmental Protection:** The "BL" designation often relates to specific finishes or sealing standards designed to resist moisture, dust, and vibration. --- ## 3. Key Applications Because of its 4PDT configuration (allowing it to control four separate circuits at once), this part is commonly found in: 1. **Avionics:** Cockpit controls where multiple redundant systems must be toggled simultaneously. 2. **Military Ground Support:** Equipment requiring ruggedized interfaces that can withstand extreme temperatures. 3. **Industrial Machinery:** Control panels where high-reliability switching is critical to safety or process continuity. --- ## 4. Operational Logic Since this is a **4PDT** switch with 3 positions, the electrical behavior is as follows: * **Position 1 (Up):** Sets 4 circuits to "ON" (Path A). * **Position 2 (Center):** Sets 4 circuits to "OFF" or a neutral state. * **Position 3 (Down):** Sets 4 circuits to "ON" (Path B). ---