FH31LA is a high-performance electric latching relay specially developed for the smart metering field, and its 80A high-current switching capability is at the leading level among similar products. The product adopts advanced magnetic retention technology, which requires only instantaneous pulse power supply to maintain the switching state, significantly reducing the energy consumption of the system, which is especially suitable for smart metering applications that require long-term operation. It is certified to the stringent IEC62052-31 standard, ensuring worldwide compliance.
80A high-current switching capability: easily copes with high load demands
High insulation performance: 4KV between contact point and coil
Low contact resistance: Initial contact resistance ≤1.0mΩ, ensuring high performance transmission.
Rapid response: opening and closing time ≤ 25ms, efficient and dependable operation.
Single-coil and dual-coil magnetic retention versions available
Various rated voltage options: DC 6V/9V/12V/24V
Flexible contact configuration: 2A (normally open) / 2B (normally closed) optional
Terminal type: pin + screw (XB) hybrid design
Compact size: 54.9 x 35 x 17.7mm, space saving
Shockproof design: functional shock resistance 98m/s² (10g), destructive shock resistance 980m/s² (100g)
Dustproof structure: flux proofed design, adaptable to harsh environment
Light weight: approx. 90g (without accessories)
Operating temperature: -40℃~85
Humidity range: 5%~85%RH
Smart Meters: Designed for smart meters to achieve accurate power consumption control and remote management functions.
New energy systems (photovoltaic/energy storage applications): for high-current switching control of solar inverters and energy storage systems.
Industrial Automation (Motor/PLC Control): Provides reliable motor start/stop and automation control solutions for industrial equipment.
Smart Home (Air Conditioning/Power Distribution Systems): meets the demand for efficient power management of air conditioning and power distribution systems in smart homes.
Railway (Train Control System): Electrical control applications that meet the harsh environmental requirements of railways.
Charging Facilities (Electric Vehicle Charging Piles): Supports high-current switching of charging piles to ensure safe and efficient charging.
The FH31LA offers both single-coil and dual-coil versions of magnetic retention to meet the needs of different application scenarios. The single-coil version has a rated power of 3W, while the dual-coil version has a rated power of 6W, both of which support four DC voltages: 6V, 9V, 12V and 24V. The single-coil version has an operating current of 0.25A and a coil resistance of 480Ω, while the dual-coil version has an operating current of 0.5A per coil and a resistance of 24Ω. All models have been designed with sufficient safety margins to allow for a maximum permissible voltage up to 1.5 times the rated value.
In practice, it is recommended that the drive voltage be 1-1.5 times the rated value and that the pulse width be not less than 100 ms. Special care should be taken not to energise the opening and closing coils at the same time and to avoid prolonged (more than 1 minute) continuous energisation. Spot soldering is recommended for the load terminals, avoid reflow or wave soldering. Due to the magnetic retention characteristics, it is recommended to confirm and reset the status after transport or installation.
As a professional relay manufacturer, Fanhar Electronics provides comprehensive customisation services for the FH31LA: including contact configuration (2A normally open or 2B normally closed), mounting method (standard PCB or customised), coil type (single/double coil), polarity selection (standard/reverse), and special pin configurations. Users can choose the most suitable product variant according to their specific application requirements.
