Dual Battery Isolator Relay – 4-Pin | 120A & 200A | 12V/24V DC

Keep your vehicle's electrical system protected and fully under control with this heavy-duty Dual Battery Isolator Relay. Designed for automotive and marine applications, this 4-pin sealed relay allows you to separate, isolate, or switch between dual battery banks — preventing drain, protecting your main battery, and giving you reliable control over your vehicle's power circuit.

Key Features

High-Capacity Current Handling: Available in 120A and 200A ratings to suit a wide range of vehicle setups, from daily drivers to heavy-duty rigs.
Wide Voltage Compatibility: Supports both DC 12V and 24V systems, making it suitable for cars, trucks, RVs, boats, and commercial vehicles.
Sealed Construction: Fully sealed housing protects internal contacts from moisture, dust, and vibration — built to last in demanding environments.
Extreme Temperature Range: Rated for operation from -40°C to +85°C, ensuring reliable performance in all climates.
Durable Materials: Constructed from high-quality plastic and metal components for long service life and consistent performance.
4-Pin Design: Standard conversion contact form (1 normally open) for straightforward integration into your vehicle's electrical system.
Easy Installation: Compact, plug-and-play design makes it simple to install in your engine bay or electrical panel.

Specifications

Material: Plastic + Metal
Color: Black
Rated Voltage: DC 12V / 24V
Nominal Current: 120A / 200A
Contact Form: Conversion type (1 normally open)
Protective Features: Sealed
Working Temperature: -40°C to +85°C
Application: Automotive / Vehicle Control Unit
Country of Origin: Made in China

What's in the Box

1 × Dual Battery Isolator Relay (4-Pin)

Perfect For

Cars, trucks, SUVs, and vans with dual battery setups
RVs and campervans needing auxiliary battery isolation
Marine and boat electrical systems
Off-road and 4WD vehicles with winches or accessory loads
Commercial vehicles and fleet electrical management

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For general guidance on automotive electrical safety and wiring standards, visit the U.S. Consumer Product Safety Commission (CPSC).

Frequently Asked Questions

Q: What is a dual battery isolator relay and why do I need one?

A: A dual battery isolator relay is an electromagnetic switch that separates two battery banks in a vehicle's electrical system. It ensures that your auxiliary battery (used for accessories like winches, lights, or camping gear) doesn't drain your main starting battery, keeping your vehicle ready to start at all times.

Q: Is this relay compatible with both 12V and 24V vehicles?

A: Yes. This isolator relay supports both DC 12V and DC 24V systems, making it compatible with a wide range of vehicles including passenger cars, trucks, RVs, boats, and commercial vehicles.

Q: What is the difference between the 120A and 200A versions?

A: The current rating determines how much electrical load the relay can safely handle. The 120A version is suitable for most standard dual-battery setups, while the 200A version is recommended for heavy-duty applications such as large winches, inverters, or high-draw auxiliary equipment.

Q: Is this relay waterproof or sealed?

A: Yes, the relay features a sealed construction that protects internal contacts from moisture, dust, and vibration — making it suitable for engine bay mounting and outdoor or marine environments.

Q: How difficult is it to install this isolator relay?

A: Installation is straightforward thanks to the standard 4-pin conversion contact design. Most users with basic automotive electrical knowledge can install it without professional assistance. Always disconnect your battery before installation and refer to your vehicle's wiring diagram for best results.