The **HFE23-AS/48-3SHT2-R** is a high-power bistable (latching) magnetic relay manufactured by Hongfa. These relays are primarily designed for smart meters, solar inverters, and industrial control systems where energy efficiency and high switching capacity are critical. --- ### 1. Part Number Breakdown Understanding the specific nomenclature helps identify the exact specifications of this component: | Code Segment | Description | Specific Detail | |:---|:---|:---| | **HFE23** | Series Name | High Power Latching Relay Series | | **AS** | Contact Type | 1 Form A (Single Pole Single Throw - NO) | | **48** | Coil Voltage | 48V DC nominal | | **3** | Coil Type | Dual Coil Latching (Two coils for Set/Reset) | | **S** | Protection | Sealed (Plastic sealed for protection) | | **H** | Contact Material | AgSnO₂ (Silver Tin Oxide) for high inrush | | **T2** | Lead Style | Specific PCB/Terminal configuration | | **-R** | Environmental | RoHS compliant | --- ### 2. Key Electronic Specifications The HFE23 series is known for its ability to handle very high currents despite its relatively compact footprint. #### **Contact Data** * **Maximum Switching Current:** Up to 80A or 100A (depending on specific sub-rating, usually 80A for this series). * **Switching Voltage:** 250V AC. * **Contact Resistance:** ≤ 1.0mΩ (Initial). * **Max Switching Power:** 20,000 VA. #### **Coil Data (48V Dual Coil)** * **Latching Mechanism:** Unlike standard relays, this requires only a short pulse (approx. 50ms) to flip states. It stays in that state without power. * **Coil Voltage:** 48V DC. * **Pulse Width:** Recommended ≥ 50ms to ensure reliable switching. --- ### 3. Core Features and Applications #### **Technical Advantages** * **Low Power Consumption:** Since it is a latching relay, it consumes zero power once the state is changed, preventing coil heating. * **High Surge Resistance:** Designed to withstand high short-circuit currents, meeting IEC 62055-31 standards. * **Safety Isolation:** Offers high dielectric strength (4kV between coil and contacts). #### **Typical Use Cases** 1. **Smart Grids:** Prepayment electricity meters. 2. **Renewable Energy:** Remote switching for solar PV inverters. 3. **EV Charging:** Power distribution control in charging piles. 4. **Industrial Automation:** Heavy load switching where heat dissipation must be minimized. --- ### 4. Connection Logic (Dual Coil) To operate this relay, you must apply voltage pulses to the specific pins: * **To Set:** Pulse applied to Coil 1 (Closes the circuit). * **To Reset:** Pulse applied to Coil 2 (Opens the circuit). * **Polarity:** Must observe the polarity indicated in the datasheet (usually marked on the relay casing).