The FH56LG is a high-performance, high-current switching single-contact relay made particularly for heavy-duty industrial use. Its main benefits are that it can switch 125A of high current, hold low-power pulses, and last for a very long time(100,000 operations) . This makes it perfect for use in severe settings where reliability is very important.
This relay has AgSnO₂ (silver oxide tin) contacts that are very resistant to arcs and welds and meet RoHS environmental regulations. When it comes to telecommunications, train transportation, new energy vehicles, maritime power, and industrial automation, it works well for electronic control systems.
Rated load: 125A @ 80VDC / 125A @ 305VAC
Maximum switching capacity: 10,000W (DC) / 38,125VA (AC)
Minimum allowable load: 5VDC 100mA (suitable for low-level signal control)
Energy-saving and environmentally friendly design, requiring only pulse excitation
No continuous power supply required: only a short pulse (200±50ms) is needed to switch and maintain the state, significantly reducing energy consumption.
Low heat generation: The coil temperature rise is smaller than with standard relays, which makes them last longer.
Wide temperature operating range: -40°C to +85°C, suitable for extreme temperature environments.
High vibration and shock resistance:
Shock resistance: 98 m/s² (10g)
Vibration resistance: 980 m/s² (100g)
Dust and splash-proof design (Flux Proofed), optional plastic-sealed version available, suitable for harsh environments containing pollutants such as H₂S, SO₂, and NO₂.
Actuation time ≤20 ms, guaranteeing rapid switching and diminished latency.
With a mechanical life of 100,000 cycles and an outstanding electrical life, it is well-suited for applications that need frequent switching.
Compact design, space-saving
Dimensions: 40×22×30mm (L×W×H)
Weight: approximately 80g, suitable for high-density PCB layouts.
The FH56LG offers two versions: single-coil self-holding (L1) and dual-coil self-holding (L2), supporting multiple voltage specifications:
The FH56LG is suitable for industrial and transportation applications requiring high current and high reliability, including:
Telecom & Data Centers
Base station power switching
Backup battery management systems
Rail Transit & Electric Vehicles
Tram/high-speed rail power control
Electric vehicle high-voltage distribution (BMS, charging control)
Industrial Automation & Power Control
High-power motor control
Industrial UPS systems
Marine & Aviation Power Systems
Marine distribution cabinets
Aircraft power management
Prior to initial use: It is advisable to administer a rated voltage pulse (≥5 times the operational duration) to confirm the relay is in the appropriate state.
Avoid concurrent excitation: The dual-coil variant must not energise both the “Set” and “Reset” coils at the same time.
PCB layout: Rigorously comply with the approved PCB dimensions (tolerance ±0.1mm) to provide adequate heat dissipation and electrical clearance.
Storage environment: Avoid high temperatures and humidity to prevent contact oxidation.
The FH56LG is a high-reliability, high-current, energy-efficient relay designed for use in severe settings such as industrial, transportation, and new energy applications. Its pulse-hold design, extremely long lifespan, and wide temperature range make it perfect for high-load applications.
For technical documentation, test reports, or custom requirements, please contact Zhejiang Fanhar Electronics Co., Ltd. or visit the official website.
