Blue Sea 90A 187-Series Surface Mount Thermal Circuit Breaker
Blue Sea 90A 187-Series Surface Mount Thermal Circuit Breaker
Ignition Protected & Weatherproof - Trip-Free Manual Reset Lever

DESCRIPTION
Heavy-Duty 90A DC Circuit Protection and Manual Switching
The Blue Sea 187-Series 90A Surface Mount Thermal Circuit Breaker delivers reliable overcurrent protection and manual switching in a single, robust unit. Engineered for demanding marine, RV, caravan, and off-grid power systems, this thermal circuit breaker simplifies electrical installations by eliminating the need for a separate battery switch and inline fuse holder. Whether you are protecting main DC feed lines, windlasses, or high-output auxiliary circuits, the 187-Series ensures dependable performance when managing heavy electrical loads.
Engineered for Safety: Trip-Free and Ignition Protected
When managing high-amperage DC circuits, safety and reliability are paramount. The Blue Sea 187-Series features a specialised trip-free design, meaning the internal mechanism cannot be manually held in the ON position while a fault current condition persists. This critical feature reduces the risk of wire overheating, insulation damage, and potential electrical fires caused by overriding a tripped breaker before the fault is resolved.
Furthermore, this unit is fully ignition protected, making it safe for installation aboard petrol-powered boats and inside marine engine compartments where flammable fumes may be present. Enclosed in a weatherproof housing, it stands up to harsh coastal environments, vibration, and moisture ingress far better than standard automotive-grade alternatives.
Key Features and Benefits
- Dual Functionality: Combines heavy-duty 90A overcurrent protection with convenient manual ON/OFF circuit switching in one compact device.
- High-Visibility Actuator: Features a large yellow manual reset lever that clearly indicates trip status at a glance and allows for straightforward operation, even in dimly lit lockers.
- Trip-Free Design: Prevents the circuit from being forced closed during an active overcurrent fault, protecting downstream cabling and equipment.
- Marine-Grade Durability: Weatherproof and ignition-protected enclosure suitable for marine engine rooms, boat hulls, and rugged 4WD canopies.
- Secure Terminations: Equipped with heavy-duty threaded stud terminals with nuts and washers to support high-current electrical ring terminals securely.
- Streamlined Mounting: Integrated recessed mounting holes allow for clean, secure surface installation onto flat distribution panels or bulkheads.
Application Considerations and Best Practices
The single-lever operation provides a clear visual indication of whether the circuit is live, manually switched off, or tripped due to an overload. Compared to replaceable fuses, a resettable thermal breaker saves time and eliminates the need to carry spare high-amp fuses on board. Please note that while this breaker is designed to serve as a convenient manual disconnect switch, it is not intended to be used as a regular switch for loads where high inrush currents are expected.
Upgrade Your Electrical Distribution System
Protect your high-current DC wiring and simplify circuit management with industry-proven hardware. Add the Blue Sea 187-Series 90A Surface Mount Thermal Circuit Breaker to your setup today for dependable, marine-grade circuit protection across your vessel or off-grid vehicle.
SKU: BS-7143B
SPECIFICATIONS
| Specification | Value |
|---|---|
| Product type | Circuit breaker |
| Mounting / form factor | Surface mount |
| Actuator type | Manual |
| Ignition protected | Yes |
| SKU: | BS-7143B |
| Model #: | BS-7143B |
| MPN: | BS-7143B |
| Package weight: | 0.36 kg |
| Package length: | 0.12 m |
| Package width: | 0.08 m |
| Package height: | 0.09 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.

