The **FCA-15-R** is a specific type of high-performance, mid-range relay manufactured by **TE Connectivity (Kilovac/Hartman brands)**. It is designed primarily for aerospace, defense, and demanding industrial applications where reliability under extreme conditions is non-negotiable. --- ### 1. General Specifications The FCA-15-R belongs to the FCA series of polarized, single-side stable relays. Below are the primary electronic and mechanical specifications: | Feature | Specification | | :--- | :--- | | **Contact Arrangement** | 1PDT (1 Form C) | | **Contact Rating** | 15 Amps | | **Coil Voltage (Nominal)** | 28 VDC | | **Terminal Style** | Solder Hooks / Terminals | | **Enclosure** | Hermetically Sealed | | **Standard Compliance** | MIL-R-6106 (Military Grade) | --- ### 2. Key Electronic Components & Construction #### A. The Coil System The relay operates on a **28 VDC** coil system. * **Polarized Design:** It uses a permanent magnet in conjunction with the electromagnet. This increases sensitivity and allows the relay to remain stable against high shocks and vibrations. * **Power Consumption:** Designed for efficiency, the coil requires minimal current to maintain the "closed" state compared to non-polarized industrial relays. #### B. Contact Assembly * **Material:** Typically uses silver-cadmium oxide or similar alloys with gold plating to prevent oxidation and ensure low contact resistance over time. * **Current Handling:** Rated for **15A at 28 VDC** or 115 VAC (400Hz). The 400Hz rating is a standard for aircraft power systems. #### C. Hermetic Sealing The internal electronic parts are housed in a metal can that is vacuum-purged and filled with an inert gas (usually dry nitrogen). * **Purpose:** Prevents internal arcing at high altitudes and protects contacts from moisture, dust, and corrosive atmospheres. --- ### 3. Applications Due to its ruggedized nature, the FCA-15-R is found in: * **Avionics:** Power distribution and engine control systems. * **Missile Systems:** Guidance and firing mechanisms. * **Space Equipment:** Satellite power switching. * **Heavy Defense Vehicles:** Communication and tactical equipment. --- ### 4. Part Number Breakdown (Typical) While "FCA-15-R" is the base series, the suffixes often denote specific mounting or wiring configurations: | Prefix | Rating | Feature | | :--- | :--- | :--- | | **FCA** | Series Name | Fixed Contact Armature | | **15** | 15 Amps | Continuous current capacity | | **R** | Configuration | Specific mounting or internal diode protection | ---