[Lifetime Warranty] 300Amp Circuit Breaker - Pack of 3
Set of three 300A waterproof circuit breakers with copper ring terminals, washers, and mounting screws.
Diagram showing 300A waterproof circuit breaker operation with push button reset and kill switch functionality.
Dimensional diagram of a 300Amp waterproof circuit breaker showing product measurements and 1/4-28 stud size.
300A waterproof circuit breaker with manual reset button and mounting holes, showing product features and specifications.
Collage showing wide application of 300Amp circuit breakers for vehicles and shipping containers.
Single 300Amp waterproof circuit breaker with battery pole connection diagram and installation hardware.
Group of friends sitting on the tailgate of a pickup truck by a lake, representing reliable 300Amp circuit breaker use.
Set of three 300A waterproof circuit breakers with copper ring terminals, washers, and mounting screws.
Diagram showing 300A waterproof circuit breaker operation with push button reset and kill switch functionality.
Dimensional diagram of a 300Amp waterproof circuit breaker showing product measurements and 1/4-28 stud size.
300A waterproof circuit breaker with manual reset button and mounting holes, showing product features and specifications.
Collage showing wide application of 300Amp circuit breakers for vehicles and shipping containers.
Single 300Amp waterproof circuit breaker with battery pole connection diagram and installation hardware.
Group of friends sitting on the tailgate of a pickup truck by a lake, representing reliable 300Amp circuit breaker use.
Lifetime Warranty

[Lifetime Warranty] 300Amp Circuit Breaker - Pack of 3

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300Amp Circuit Breaker - Pack of 3

Key Features

  • Current Rating: 300 Amps
  • Voltage Range: DC 12V - 48V
  • Trip Mechanism: Thermal
  • Reset Type: Manual push-button reset switch; also functions as a master disconnect
  • Housing: High-temperature rated, water-resistant enclosure
  • Terminals: #10-32 stainless steel threaded studs
  • Mounting: Surface mount with two mounting holes
  • Quantity: Includes three individual 300A circuit breakers

Replaces / Cross-Reference Part Numbers

  • Can be used as a direct replacement for Bussmann CB285-300 and CB185-300
  • Interchangeable with Blue Sea Systems 7189 and 187-Series 300A breakers
  • Replaces similar style surface-mount, manual reset breakers used in automotive and marine applications

Compatibility & Fitment

  • Designed for high-current DC electrical systems
  • Automotive: Car audio amplifiers, secondary battery systems
  • Marine: Trolling motors, anchor winches, bow thrusters
  • Recreational Vehicles (RV): Inverter connections, battery banks, solar charge controllers
  • Industrial: Heavy equipment, DC motor circuits

When to Replace

  • Existing breaker fails to trip during an overcurrent or short-circuit event
  • Breaker trips repeatedly under a known, safe load (nuisance tripping)
  • The manual reset lever or button is physically broken or will not stay engaged
  • Visible signs of heat damage, melting, or cracks in the housing
  • Terminals are heavily corroded, preventing a secure electrical connection

Installation Tips

  • Disconnect the main power source (battery negative terminal) before beginning installation
  • Install the breaker as close to the power source as possible for maximum protection
  • Use correct wire gauge (AWG) rated for 300A to prevent wire overheating
  • Ensure all cable lug connections are clean and torqued securely to the studs
  • Mount in a location that provides protection from direct, high-pressure water spray and excessive engine heat
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  • Manual Reset Switch

    Manual Reset Switch

    Simple manual control with reset arm, serving as both a switch for battery/DC sound amplifier system
  • Superior Quality

    Superior Quality

    Premium steel studs are stainless with protective stud insulators included.
  • Waterproof Level IP67

    Waterproof Level IP67

    This product adopts I P67 waterproof thermal-plastic mount cover ensuring long life service.
  • Package Include

    Package Include

    3 x 300Amp Circuit Breaker
BRINGING RELIABILITY TO THE SWITCH

BRINGING RELIABILITY TO THE SWITCH

Brand Model Number
Model 300 Amp Circuit Breaker
Voltage Rating 12-48V DC
Interrupt Capacity 3KA@48VDC

FAQ

These breakers are designed for high-amperage DC electrical systems, commonly used in marine trolling motors, automotive audio systems, RVs, solar power setups, and battery charging systems. They provide essential overcurrent protection for heavy-duty circuits.
These are manual reset breakers. If the circuit is overloaded, the internal mechanism will trip and the manual reset lever will flip to the 'off' position. You can visually inspect the lever to confirm if it has tripped.
Once the fault in your electrical system has been identified and corrected, simply push the manual reset lever back into the 'on' position. There is no need to replace a fuse; the breaker is designed to be reusable.
Yes, these breakers are compatible with a wide range of DC voltages, typically handling up to 48V DC. They are suitable for standard 12V, 24V, and 36V battery systems.
Ensure that your wire gauge is properly sized for a 300-amp load. Using wire that is too thin for this amperage can lead to excessive heat and voltage drop. Additionally, always mount the breaker in a dry, accessible location to ensure the manual reset lever can be reached easily.
While the manual reset lever can be used to disconnect the circuit for maintenance, it is primarily designed as a protective device. It is not intended to be used as a frequent power switch for daily operation.