### Overview: LPS-RK-35SP Low-Peak Fuse The **LPS-RK-35SP** is a high-performance, current-limiting, time-delay power fuse. It belongs to the **Bussmann series (by Eaton)** and is classified under **UL Class RK1**. This specific model is designed for heavy-duty industrial and commercial electrical systems. --- ### Technical Specifications | Feature | Specification | | :--- | :--- | | **Manufacturer** | Eaton (Bussmann Series) | | **Model Number** | LPS-RK-35SP | | **Amperage Rating** | 35 Amps | | **Voltage Rating (AC)** | 600 Vac (or less) | | **Voltage Rating (DC)** | 300 Vdc (or less) | | **Interrupting Rating** | 300kA RMS Symmetrical (AC) / 100kA (DC) | | **Class** | RK1 | | **Response Time** | Time-Delay (Dual-Element) | --- ### Key Electronic & Functional Components #### 1. Dual-Element Design Unlike a standard fast-acting fuse, the LPS-RK-35SP features two distinct internal components: * **The Thermal Element:** Handles low-level overloads. It has a specific time-lag feature that allows temporary surges (like motor startups) to pass without blowing the fuse. * **The Magnetic/Instantaneous Element:** Designed to react immediately to high-level short circuits to prevent catastrophic equipment damage. #### 2. Current Limitation As a **Class RK1** fuse, it is significantly more current-limiting than Class RK5 or Class H fuses. In the event of a short circuit, it clears the fault so quickly that it prevents the peak current from ever reaching its full potential, protecting downstream components like motor starters and circuit breakers. #### 3. Material Composition * **Body:** High-grade melamine or fiberglass tube for superior arc-quenching and thermal stability. * **End Caps:** Heavy-duty bronze or copper alloy with silver or tin plating to ensure high conductivity and corrosion resistance. --- ### Primary Applications * **Motor Circuits:** Ideal for motors with high inrush current. * **Transformers:** Protects against secondary short circuits. * **Panelboards:** Used in main or branch circuit protection where high interrupting capacity is required. * **Inductive Loads:** Any circuit with solenoids or large coils that create temporary current spikes. --- ### Comparison: LPS-RK (RK1) vs. FRN-R (RK5) | Feature | LPS-RK-35SP (RK1) | FRN-R-35 (RK5) | | :--- | :--- | :--- | | **Protection Level** | Superior Current Limitation | Standard Protection | | **Voltage** | 600V AC | 250V AC | | **Interrupting Rating** | 300,000 Amps | 200,000 Amps | | **Best Use** | Critical sensitive electronics | General purpose motor loads | ---