The **HFE19-60/24-HT-1-R** is a high-power, polarized bistable (latching) magnetic relay specifically designed for applications requiring high switching capacity and energy efficiency, such as smart meters and industrial control systems. --- ### 1. Part Number Breakdown Understanding the nomenclature helps define the electrical characteristics: | Code Segment | Meaning | Specification | | :--- | :--- | :--- | | **HFE19** | Series Name | Hongfa High Power Latching Relay | | **60** | Contact Rating | 60A Switching Capability | | **24** | Coil Voltage | 24VDC Nominal | | **H** | Contact Form | 1 Form A (Normally Open) | | **T** | Contact Material | AgSnO₂ (Silver Tin Oxide) | | **1** | Coil Type | Single Coil Latching | | **R** | Polarity | Reverse Polarity (Standard) | --- ### 2. Key Electrical Specifications The device is engineered to handle significant electrical loads while consuming zero power once the state has been switched. #### Contact Data * **Max Switching Current:** 60A * **Max Switching Voltage:** 250VAC * **Contact Resistance:** < 2.0 mΩ (initial) * **Mechanical Endurance:** 1,000,000 cycles * **Electrical Endurance:** 10,000 cycles (at rated load) #### Coil Data (Latching Mechanism) Because this is a **latching relay**, it uses a permanent magnet to hold the contacts in place. * **Nominal Voltage:** 24VDC * **Pulse Duration:** Requires a pulse of ≥100ms to switch states. * **Pick-up Voltage:** ≤16.8VDC * **Coil Power:** Approx. 1.5W (only during the pulse). --- ### 3. Electronic Design Considerations #### Latching Control Unlike standard relays, you cannot apply continuous voltage. You must use a H-bridge circuit or a specialized driver to provide a momentary pulse. To reverse the state (from ON to OFF), you must reverse the polarity of the pulse across the coil. #### Contact Material (AgSnO₂) The use of Silver Tin Oxide (AgSnO₂) is critical for the "60A" rating. This material provides: * Excellent resistance to welding (sticking). * High erosion resistance during high-inrush current events. * Environmentally friendly (Cadmium-free). #### Insulation & Safety * **Dielectric Strength:** 4,000VAC (between coil and contacts). * **Creepage Distance:** 8mm, providing high isolation for safety-critical applications. --- ### 4. Typical Applications * **Smart Grids:** Remote disconnection/connection of electricity meters. * **Renewable Energy:** Inverters and solar tracking systems. * **EV Charging:** Level 1 or Level 2 AC charging stations. * **Industrial Automation:** Heavy load switching with low standby power requirements.