Description
Blue Sea 7146 120A Thermal Breaker | Boat Supply Store
Safeguard demanding marine DC systems against overcurrent conditions and provide integrated switching functionality with the Blue Sea 7146 187-Series Thermal Circuit Breaker. This unit is ignition protected per SAE J1171, making it suitable for gasoline-powered vessels where spark prevention is critical, and features a trip-free design to prevent manual defeat of protection. With a robust 120 Amp rating and a 5,000 Amp @ 12 Volts DC interrupt capacity, it ensures reliable operation for high-draw applications within 12V, 24V, or 42V DC systems.
Key Features
- Combines switching and circuit protection for system simplification.
- Meets SAE J1171 external ignition protection requirements, crucial for gasoline engines.
- Features clear, single lever operation for intuitive control and status indication.
- Ensures safety with a trip-free design that cannot be manually held closed during a fault.
- Provides waterproof integrity for reliable performance in harsh marine environments.
- Offers recessed mounting holes for a clean, integrated installation aesthetic.
- Accommodates substantial wiring with robust 5/16" terminal studs and ample clearance.
- Delivers visible trip indication with a large lever offering vertical or horizontal orientation.
Specifications
| Product Specifications | |
|---|---|
| Amperage Rating | 120 Amp |
| Series | 187-Series |
| Type | Type III (Switchable/Manual Reset/Trip Free) |
| Actuator Type | Thermally Responsive Bi-Metal Blade |
| Case Material | Thermoset Polyester |
| Maximum Voltage | 48 Volts DC |
| Interrupt Rating @ 12 Volts DC | 5,000 Amperes |
| Interrupt Rating @ 24 Volts DC | 3,000 Amperes |
| Interrupt Rating @ 42 Volts DC | 1,500 Amperes |
| Operating Temperature Range | -25°C to +82°C |
| Ignition Protection | SAE J1171 |
Who This Is For
Marine enthusiasts, boat owners, and marine electricians requiring reliable and integrated circuit protection and switching for 12V, 24V, or 42V DC systems. This breaker is especially critical for gasoline-powered vessels where SAE J1171 ignition protection is a mandated safety feature.
How It Compares
| Feature | Blue Sea 7146 120A Thermal Breaker | Blue Sea Systems 7087 187 Series Thermal Circuit Breaker |
|---|---|---|
| Amperage Rating | 120 Amp | 100 Amp |
| Voltage Rating (Max) | 48 Volts DC | 48 Volts DC, 24 Volts DC |
| Ignition Protected | Yes (SAE J1171) | Yes, Yes |
| Interrupt Rating @ 12V DC | 5,000 Amperes | 5,000 Amperes, 2,500 Amperes |
| Trip Free Design | Yes | Yes, Yes |
Common Concerns Answered
Can I use a lower amperage circuit breaker if my device draws less than 120 amps?
While a lower amperage breaker can protect a circuit, ensure it is correctly sized for the continuous load of your equipment according to ABYC standards and manufacturer recommendations. Using a breaker with an excessively low rating can lead to nuisance tripping, whereas a breaker with an insufficient rating will not provide adequate protection.
Is the price of the Blue Sea 7146 higher than other circuit breakers?
The Blue Sea 7146 offers integrated switching and superior ignition protection (SAE J1171), features not present in many basic thermal circuit breakers. This premium functionality, combined with robust construction and a trip-free design, justifies its position in a higher price bracket, particularly for critical applications where safety and reliability are paramount.
What are the risks of improper installation?
Improper installation, including incorrect wire sizing or loose terminal connections, can lead to overheating, reduced circuit protection effectiveness, or even fire hazards. Adhering strictly to the manual's wiring diagrams and ensuring all connections are secure and torqued correctly is vital for safe operation, especially on vessels with gasoline engines.
Frequently Asked Questions
What is the voltage rating of the Blue Sea 7146 circuit breaker?
The Blue Sea 7146 circuit breaker has a maximum voltage rating of 48 Volts DC.
What is the interrupt rating of the Blue Sea 7146 circuit breaker?
The interrupt rating varies by voltage: 5,000 Amperes @ 12 Volts DC, 3,000 Amperes @ 24 Volts DC, and 1,500 Amperes @ 42 Volts DC.
Is the Blue Sea 7146 circuit breaker ignition protected?
Yes, the Blue Sea 7146 circuit breaker meets SAE J1171 external ignition protection requirements, making it suitable for use in gasoline-powered vessels.
What type of reset does the Blue Sea 7146 circuit breaker have?
The Blue Sea 7146 features a Type III design, which includes manual reset and a trip-free mechanism.
Can the Blue Sea 7146 circuit breaker be used on gasoline-powered boats?
Yes, the Blue Sea 7146 is explicitly designed for use on gasoline-powered boats due to its SAE J1171 ignition protection, which prevents ignition of surrounding flammable vapors.
