The **W2SP-2B3-R/UL** is a high-performance, UL-recognized thermal circuit breaker, typically part of the **W2 series** manufactured by brands like **Schurter** or **Tyco Electronics (TE Connectivity)**. It is designed to provide overcurrent protection for equipment and machinery. --- ### ## Technical Specifications Below are the primary electronic and mechanical characteristics of the W2SP-2B3-R/UL: | Property | Description | | :--- | :--- | | **Type** | Thermal Circuit Breaker (Press-to-Reset) | | **Poles** | Single Pole (1-Pole) | | **Rated Voltage** | 250 VAC / 32 VDC (typical) | | **Current Rating** | 3A (Standard for "3" in the code) | | **Mounting Type** | Panel Mount (Snap-in or Threaded neck) | | **Termination** | Quick Connect / Solder terminals | | **Approvals** | UL 1077 (Supplementary Protectors) | --- ### ## Key Electronic Features ### 1. Thermal Sensing Element The device utilizes a **bimetallic strip**. When current flows through the strip, it generates heat. If the current exceeds the rated 3A for a specific duration, the bimetal bends due to the difference in expansion rates of the two metals, triggering the mechanical latch to open the circuit. ### 2. Reset Mechanism (R/UL Designation) * **Manual Reset:** This is a "Trip-Free" design. If an overload persists, the breaker cannot be forced to stay closed by holding the button down. * **Visual Indication:** The button usually pops out when the breaker trips, providing a clear visual status of the fault. ### 3. Protection Characteristics * **Time-Delay:** Unlike magnetic breakers that trip instantly, thermal breakers have a time-delay characteristic. They ignore short "inrush" currents (like a motor starting up) but trip on sustained overloads. * **Interrupt Capacity:** Designed to handle moderate short-circuit currents (typically up to 1000A or 2000A depending on the specific sub-series). --- ### ## Application Context The "UL" suffix signifies that the part meets **UL 1077** standards, making it suitable for use as a supplementary protector in: * Industrial control panels. * Medical diagnostic equipment. * Power supplies and UPS systems. * Household appliances. --- ### ## Connection Diagram (Conceptual) ```text [ Line In ] ----[ Bimetal Element ]----[ Latch ]---- [ Load Out ] | [ Reset Button ] ```