The **ESD-R-25SH** is a high-performance, clamp-on EMI core (ferrite core) manufactured by **KEMET**. These components are specifically designed to suppress electromagnetic interference (EMI) and noise in electrical systems without requiring the cable to be disconnected. --- ### 1. Technical Specifications Below are the primary physical and electrical characteristics of the ESD-R-25SH: | Feature | Specification | | :--- | :--- | | **Material** | Manganese-Zinc (Mn-Zn) | | **Shape** | Round / Toroidal (Split Core) | | **Inner Diameter (ID)** | 13.0 mm | | **Outer Diameter (OD)** | 29.5 mm | | **Height (H)** | 13.5 mm | | **Frequency Range** | Low to Mid Frequency (Broadband) | | **Configuration** | Split-core with plastic case/shroud | --- ### 2. Key Features * **Split-Core Design:** The "SH" suffix indicates a split configuration housed in a plastic case. This allows the core to be snapped onto existing cables (retrofitting) without cutting or soldering. * **Mn-Zn Material:** Unlike Nickel-Zinc (Ni-Zn) cores which handle high frequencies, Mn-Zn ferrites are optimized for high magnetic permeability and are more effective at suppressing noise in lower frequency bands. * **Integrated Clip:** The plastic housing includes a locking mechanism that ensures the two halves of the ferrite are held tightly together, minimizing the air gap and maximizing impedance. --- ### 3. Functional Application The ESD-R-25SH works by adding **impedance** to a cable for high-frequency signals while remaining "invisible" to low-frequency power or data signals. * **Common Mode Choke:** It acts as a common-mode choke, absorbing high-frequency noise and dissipating it as a tiny amount of heat. * **Typical Uses:** * Consumer electronics (TVs, PCs). * Industrial equipment power lines. * Reducing noise emission on signal cables to meet EMC compliance standards. --- ### 4. Installation Best Practices To maximize the effectiveness of the ESD-R-25SH: 1. **Placement:** Place the core as close to the noise source or the entry point of the device as possible. 2. **Cable Fit:** Ensure the cable diameter is close to the 13.0 mm inner diameter. If the cable is too thin, it can be looped through the core multiple times (turns) to increase impedance. 3. **Impedance Rule:** Impedance increases with the square of the number of turns: * $1 \text{ turn} = Z$ * $2 \text{ turns} = 4Z$