Based on the part number **18KVS-666-R**, this component is typically identified as a **High-Voltage Reed Relay** manufactured by **MEDER electronic** (now part of **Standex Electronics**). These relays are designed for applications requiring high dielectric strength and reliable switching of high voltages in a compact form factor. --- ### 1. Technical Specifications The "18" in the series often refers to the coil voltage or a specific series designator, while "666" relates to the contact configuration and voltage rating. | Feature | Specification (Typical) | | :--- | :--- | | **Contact Form** | Form A (Normally Open) | | **Max Switching Voltage** | Up to 10,000 VDC | | **Max Breakdown Voltage** | Up to 15,000 VDC | | **Contact Rating** | 50 - 100 Watts | | **Coil Voltage** | Typically 12V or 24V DC | | **Insulation Resistance** | > $10^{12}$ $\Omega$ | | **Housing** | Potted / Encapsulated for HV insulation | --- ### 2. Key Internal Components The 18KVS series utilizes specific electronic and mechanical parts to handle extreme electrical stress: * **Hermetically Sealed Reed Switch:** The core component consists of two ferromagnetic blades in a glass envelope filled with inert gas. This prevents arcing and oxidation. * **Copper Coil:** Wrapped around the reed switch. When energized, it creates a magnetic field that pulls the reed contacts together. * **Encapsulation Compound:** Usually a high-grade epoxy or silicone potting. This provides the "KVS" (High Voltage Series) designation, ensuring no arcing occurs between the pins outside the glass. * **Tungsten or Rhodium Contacts:** The contact tips are often plated with heavy metals to withstand the "pitting" caused by high-voltage sparks during switching. --- ### 3. Common Applications Due to its high insulation properties, the **18KVS-666-R** is used in: * **Automated Test Equipment (ATE):** Testing insulation and cable harnesses. * **Medical Equipment:** Defibrillators and imaging machines. * **EV Battery Testing:** Managing high-voltage strings in electric vehicle batteries. * **Mass Spectrometry:** Precise switching of ion-source voltages. --- ### 4. Circuit Diagram Representation In a schematic, this part is represented as a standard relay with a high-voltage barrier: ```text Coil Pins High Voltage Pins [ Pin 1 ]----(S)----[ Pin 2 ] | |-----------| Input ---|--/ /-----|--- Output |-----------| (Reed Switch) ```