Automotive Power Relay FUJITSU FBR51ND12-W1 — 1-pole changeover, 12 V DC, max 25 A, max 30 V AC

This FUJITSU FBR51ND12-W1 automotive power relay is a compact 1-pole changeover device designed for 12 V DC electrical systems. It provides a single pole double throw contact arrangement suitable for switching loads in low-voltage automotive and industrial environments. The relay is specified for a maximum switching current of 25 A and can handle AC voltages up to 30 V, making it suitable for controlling lights, small motors, valves and auxiliary circuits where a reliable electromechanical switch is required.

Advantages

The relay combines a compact footprint with a robust contact rating that supports moderate current loads up to 25 A. Its changeover contact configuration allows switching between two circuits or providing normally open and normally closed functionality in one unit. Designed for 12 V DC coil operation, the relay integrates easily into standard automotive electrical systems and low-voltage control panels. The device offers dependable mechanical switching behavior, straightforward wiring and compatibility with common mounting and socket solutions.

Suitable for

• Switching automotive lighting circuits (headlights, auxiliary lamps)
• Controlling small DC motors and fans
• Operating solenoid valves and actuators in low-voltage systems
• Protecting and switching auxiliary circuits and accessories
• Replacement or retrofit in 12 V relay sockets

Key specifications

• Contact configuration: 1-pole changeover (SPDT)
• Rated coil voltage: 12 V DC
• Maximum switching current: 25 A
• Maximum AC voltage across contacts: 30 V AC
• Intended application: automotive and low-voltage industrial switching
• Mounting: compatible with standard relay sockets (check pinout and footprint)

How to use

Install the relay into a compatible socket or secure it according to the vehicle or equipment manufacturer's guidance, ensuring correct orientation and firm electrical connections. Connect the coil to a stable 12 V DC supply with appropriate control wiring, and route load circuits through the common and normally open or normally closed contacts as required by the application. Verify wiring polarity and use proper fusing sized for the maximum expected current to protect wiring and the relay contacts. After installation, perform functional checks by energizing the coil and confirming correct switching behavior under load.

Usage recommendations

Use a fuse or circuit breaker rated slightly above the expected operating current but within the relay's 25 A maximum. Avoid switching inductive loads without appropriate suppression (diodes, RC snubbers or surge protection) to extend contact life. Ensure contact ratings and voltage limits match the intended application; for higher voltages or currents select a relay with appropriate specifications.