W27LA series relays are highly reliable electromechanical relays developed by Zhejiang Fanhar Electronics Co., Ltd. for harsh industrial environments. As the core switching component for new photovoltaic energy and industrial control, this product combines high load capacity, long electrical life and excellent environmental adaptability, and fully complies with the international photovoltaic standard VDE0126 and many safety certification requirements. Its innovative contact design, optimized electromagnetic system and robust mechanical structure make it an ideal choice to replace traditional contactors, especially for application scenarios requiring frequent switching and high reliability.
High switching capacity: 120A maximum switching current with 440VAC maximum switching voltage, easily coping with all kinds of heavy-duty applications.
Optimized contact system: AgSnO₂ (Silver Tin Oxide) composite material is used, with a contact resistance of ≤1mΩ (under 6VDC 1A test conditions), effectively reducing energy consumption and temperature rise.
Double insulation guarantee: 2500VAC/1min between contacts, coil to contact Double insulation guarantee: 2500VAC/1min between contacts and 4000VAC/1min between coil and contacts, far exceeding the industry standard.
Extremely fast response: ≤25ms closing/disconnecting time, ensuring accurate and real-time system control.
Powerful DC processing capability: specially strengthened DC60V/35A load capacity, perfectly adapted to the needs of photovoltaic systems.
Long mechanical life: 1 million times mechanical operation life verification, to ensure long-term stable operation
Rigorous environmental adaptability: -40℃~95℃ wide temperature operating range, 5%-95% humidity range, adapt to all kinds of harsh environments
Excellent vibration resistance: through the 10Hz~55Hz/1.5mm displacement amplitude vibration test, 98m/s² (10g) functional impact test
Dual Certification Guarantee: UL/C-UL (E475405) and TUV (R50412805) international safety certificates
Environmentally Compliant Design: All series comply with the requirements of the RoHS directive, and do not contain restricted substances.
Professional photovoltaic certification: contact gap ≥3mm design, fully compliant with VDE0126 standard for photovoltaic applications
DC special enhancement: specially optimized arc extinguishing system ensures reliable disconnection under DC60V/35A loads
Multiple mounting configurations: provide two PCB mounting modes of type A/type B, suitable for different system layouts
Flexible control options: single/double coil blocking is optional, supporting manual control switch operation. Flexible control options: single/dual coil latching selectable, manual control switch operation supported
Switching Control on DC Input Side of PV Inverters
String Isolation Protection for String Inverters
Emergency Shutdown Devices for PV Arrays
Circuit Protection in DC Combiner Boxes
Power extension of PLC output modules
Main contactors for motor control circuits
Power switching of automation equipment
Electrical control systems for heavy machinery
Charge/discharge control of battery storage systems
Circuit switching of uninterruptible power supplies (UPS)
Automatic switching devices for distribution systems
Power management of new energy charging piles
Railway Auxiliary Control Systems
Marine Power Management Systems
Power Switching for Military Electronics
Industrial Control in Harsh Environments
Preferred for photovoltaic applications: single-coil latching type (L1) + AgSnO₂ contact (T) combination is recommended to ensure DC breaking reliability
Recommended for industrial control: double-coil latching type (L2) is better suited for occasions that require definite state retention
High-vibration environments: select the vibration-enhanced version with B-type mounting structure (coded with a 2 in the third digit)
Special requirements: auxiliary contacts, special coatings, etc. can be customized through customer code segments Special requirements: Auxiliary contacts, special coatings, etc. can be customized with customer code segments.
PCB Layout Suggestions:
Maintain ≥5mm heat dissipation space around the relay
Maintain ≥8mm spacing between the high voltage lines and other signal lines
Recommended to use PCB boards with 2oz and above copper thickness
Soldering Process:
Wave Soldering: Recommended to be 245±5℃, contact time ≤5s
Manual Soldering: Use 30-60W soldering iron, single-point soldering time ≤3s
Avoid the use of acid flux
Mechanical Installation:
Avoid applying more than 50N to the enclosure when installing. Avoid applying more than 50N pressure to the housing
M3 screws with a torque of 0.5N-m are recommended
Avoid arranging components above the relay that may drip liquids
Preparation for Initial Use:
Apply rated coil voltage pulses (width ≥125ms) for condition reset before first use
5-10 no-load operations are recommended to break in contacts
Monitoring of Operation:
Regularly check contact resistance (every 1000 operations are recommended)
Monitor the coil operating current, and check it if the deviation is more than ±15%
Pay attention to listening for abnormal operation sounds
Life Management:
Under rated load, full testing is recommended after every 10,000 operations. A full inspection is recommended after every 10,000 operations under rated load.
Preventive replacement should be considered when 80% of the electrical life is reached.
Establish a file on the use of the relay to record the number of operations and environmental conditions.
Certificates and Standards
Safety Certificates: UL/C-UL (E475405), TUV (R50412805).
Environmental Certificates: RoHS, REACH fully compliant.
Industry Standards: IEC 61810-1, IEC 61810-1, IEC 61810-1, IEC 61810-1, TUV (R50412805). IEC 61810-1, GB/T 21711.1 and other international and domestic standards
Photovoltaic special: meet VDE0126, IEC 62109 and other photovoltaic equipment standards
Contact Us
Zhejiang Fanhar Electronics Co., Ltd. is committed to providing customers with the most reliable relay solutions. Our engineering team is ready to provide you with technical support, application consulting and customization services.
