Solar Panels
Solar Controllers
Batteries
Inverters
Mains Chargers
DC-DC Chargers
Cables/Accessories
Power Converters
Monitoring
Kits
By Application
By Brand
Blue Sea 120A 187-Series Surface Mount Thermal Circuit Breaker
Blue Sea 120A 187-Series Surface Mount Thermal Circuit Breaker
Ignition Protected, Trip-Free Reset Lever & 5/16" (M8) Terminal Studs
Regular price
$167.82
Availability:
Special Order
View all products from Blue Sea
Guaranteed Safe and Secure Checkout
0
DESCRIPTION
Integrated 120A Overcurrent Protection and Manual Battery Switching
The Blue Sea 187-Series 120A Surface Mount Thermal Circuit Breaker delivers dependable electrical protection and manual switching in a single, consolidated unit. Designed for demanding marine, 4WD, caravan, and off-grid power architectures, this heavy-duty breaker eliminates the need to wire separate fuse holders and battery isolation switches. By combining both functions into one compact surface-mount footprint, it simplifies installation, reduces potential failure points in your wiring loom, and saves valuable bulkhead or panel space.
Unlike standard inline fuses that require spare components when a fault occurs, this resettable thermal circuit breaker features a prominent, high-visibility yellow reset lever. The lever provides an immediate visual indication of the trip status and allows for straightforward manual resets or deliberate circuit isolation during routine system maintenance. Furthermore, the housing is designed so the lever can be oriented for either vertical or horizontal mounting layouts, offering clear readability regardless of your installation constraints.
Key Features and Technical Benefits
- Dual-Function Design: Combines 120A thermal overcurrent protection and manual ON/OFF circuit switching in one robust device.
- Trip-Free Operation: Internal safety mechanism ensures the breaker cannot be manually held in the ON position while a dangerous fault current persists.
- Ignition Protected: Engineered within a sealed, weatherproof housing that is safe for installation aboard petrol-powered marine vessels and near vented battery compartments.
- Heavy-Duty Terminal Studs: Equipped with robust 5/16" (Approx. M8) stainless steel terminal studs that provide ample clearance for heavy-gauge cable lugs and support high-torque connections.
- High-Visibility Lever: Large yellow actuator clearly displays whether the circuit is active, tripped, or manually isolated, and suits both vertical and horizontal orientations.
- Surface Mount Form Factor: Pre-drilled mounting holes allow for straightforward, secure attachment directly to flat panels, battery boxes, or bulkheads.
Engineered for Safety and High-Torque Reliability
When working with high-amperage DC systems, poor electrical connections and substandard protection hardware can lead to severe voltage drop, melted housings, and thermal hazards. The Blue Sea 187-Series mitigates these risks through precision engineering. Its trip-free mechanism is a critical safety asset; if a short circuit or overload occurs down the line, the internal thermal element will trip and physically prevent the user from forcing the circuit closed until the fault is resolved and the unit has cooled.
In harsh marine and mobile environments, moisture ingress and vibration often degrade standard electrical connections. This breaker features a weatherproof housing that shields internal components from dust and water spray. The 5/16" (Approx. M8) stainless steel studs resist corrosion and allow installers to apply proper torque specifications without stripping threads, ensuring a low-resistance connection that handles continuous heavy loads cleanly.
Application Guidelines and Exclusions
This 120A thermal breaker is well suited for protecting main DC feed wires, high-output alternator charge lines, auxiliary battery banks, and windlass or bow thruster circuits. Its ignition-protected rating makes it particularly valuable for boat builders and marine electricians working around inboard petrol engine bays.
Important Application Note: Do not use this circuit breaker as a frequent manual switch in applications where high inrush currents are expected, such as directly switching large power inverters without pre-charge circuitry, as repeated high-inrush switching can prematurely wear the internal contacts.
Upgrade Your Electrical Protection
Equip your marine vessel, caravan, or off-grid power system with professional-grade overcurrent protection. Add the Blue Sea 187-Series 120A Surface Mount Thermal Circuit Breaker to your setup today for safe, resettable circuit management.
SKU: BS-7146B
SPECIFICATIONS
| Specification | Value |
|---|---|
| Component subtype | Circuit breaker |
| Mounting / form factor | Surface mount |
| SKU: | BS-7146B |
| Model #: | BS-7146B |
| MPN: | BS-7146B |
| Package weight: | 0.3 kg |
| Package length: | 0.1 m |
| Package width: | 0.09 m |
| Package height: | 0.08 m |
WARRANTY
Blue Sea Warranty Policy
Blue Sea Systems products sold by us are supplied with a warranty against defects for the warranty period shown below, subject to the product type, application and the terms of this warranty policy.
The express warranty provided by us is limited to a maximum of 5 years from the original date of purchase, unless otherwise required under Australian Consumer Law.
Blue Sea Systems may offer longer manufacturer support on some products at their discretion
Warranty Lengths by Product Range
| Blue Sea Product Range | Warranty Length | Application / Notes |
|---|---|---|
| Most Blue Sea Systems Products | 5 years | Applies to most Blue Sea Systems products found to be defective in materials or manufacture. |
| P12 Battery Chargers | 5 years | Warranty period starts from the original date of purchase. |
| P12 Remote Displays | 5 years | Warranty period starts from the original date of purchase. |
| Digital Meters | 3 years | Warranty period starts from the original date of purchase. |
| Vessel System Monitors | 3 years | Warranty period starts from the original date of purchase. |
Warranty Assessment and Remedy
If a Blue Sea Systems product is found to be defective in materials or manufacture within the applicable warranty period, we will, at our discretion, arrange a repair, replacement, store credit or refund, depending on the nature of the fault and the requirements of Australian Consumer Law.
Products may need to be returned for assessment before a warranty claim can be approved. Where required, the product must be returned with dated proof of purchase and a clear description of the fault.
Labour costs for removing, replacing, reinstalling or diagnosing a product are not covered by this express warranty unless otherwise required under Australian Consumer Law.
Making a Warranty Claim
To make a warranty claim, please contact us with your dated proof of purchase, product details and a description of the fault.
The product may need to be returned for inspection before the claim can be assessed. If the product is confirmed to be faulty and covered by this warranty, we will advise the available remedy.
What This Warranty Does Not Cover
This warranty does not cover faults or damage caused by incorrect installation, incorrect application, misuse, abuse, neglect, unauthorised modification, accidental damage, normal wear and tear, environmental damage, or failure to use the product in accordance with the manufacturer's instructions.
- Incorrect installation or wiring
- Incorrect product selection or application
- Misuse, abuse or neglect
- Physical or accidental damage
- Water ingress or environmental damage outside the product's intended use
- Unauthorised modification or repair
- Normal wear and tear
- Labour costs for removal, replacement, reinstallation or diagnosis
- Freight, travel or call-out costs unless otherwise required by law
- Products not returned for assessment when reasonably required
Manufacturer Support
Blue Sea Systems may provide additional manufacturer support on some products beyond the warranty period listed above. Where available, we may assist customers in contacting the manufacturer, but any manufacturer support beyond the express warranty period is subject to the manufacturer's own terms and continued availability.
Australian Consumer Law
This warranty is in addition to other rights and remedies available at law. Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure.
DOCUMENTS
Loading product documents…