The **7101L40CWCQE** is a specific part number for a subminiature toggle switch manufactured by **C&K** (now part of Littelfuse). This component belongs to the **7000 Series**, which is widely used in industrial, medical, and telecommunications equipment. ### 1. Part Number Breakdown The nomenclature of this part explains its electrical and mechanical characteristics: | Code Segment | Feature | Description | | :--- | :--- | :--- | | **7101** | Function | SPDT (Single Pole Double Throw) On-On | | **L40** | Actuator | Lever handle, Anti-rotation, 0.530" high | | **CW** | Bushing | Threaded, 0.250" high, with keyway | | **C** | Terminations | PC Thru-hole (Printed Circuit) | | **Q** | Contact Material | Silver (Power Rating) | | **E** | Seal | Epoxy sealed (prevents flux contamination) | --- ### 2. Technical Specifications This switch is designed for both signal and power switching applications. * **Contact Rating:** 5 Amps @ 120 V AC or 28 V DC; 2 Amps @ 250 V AC. * **Electrical Life:** 40,000 make-and-break cycles at full load. * **Contact Resistance:** Below 10 mΩ (initial). * **Insulation Resistance:** 10⁹ Ω minimum. * **Dielectric Strength:** 1,000 Vrms @ sea level. * **Operating Temperature:** -30°C to +85°C. --- ### 3. Physical Construction The materials used in the 7101L40CWCQE ensure durability and reliable electrical contact: 1. **Case:** Glass-filled nylon 6/6, flame retardant, heat stabilized (UL 94V-0). 2. **Actuator:** Chrome-plated brass. 3. **Contacts:** Silver plated (indicated by the 'Q' in the part number). 4. **Terminal Seal:** Epoxy. This is crucial during the soldering process as it prevents solder flux from entering the internal switch mechanism. --- ### 4. Application Use Cases Because of its **SPDT On-On** configuration, this switch is typically used for: * **Power Routing:** Switching between two different power sources. * **Function Selection:** Toggling between two operating modes in a device. * **Control Panels:** Standard user-interface toggle for industrial machinery. ---