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Blue Sea 50A 187-Series Surface Mount Thermal Circuit Breaker
Blue Sea 50A 187-Series Surface Mount Thermal Circuit Breaker
Waterproof, Ignition Protected, 48V DC Max with 5/16" (M8) Studs
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$167.82
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DESCRIPTION
Heavy-Duty 50A DC Circuit Protection and Switching for Marine and Off-Grid Systems
The Blue Sea 187-Series 50A Surface Mount Thermal Circuit Breaker delivers reliable overcurrent protection and manual switching in a single, compact unit. Engineered specifically for demanding 12V, 24V, and up to 48V DC electrical systems, this breaker eliminates the need for separate fuse blocks and isolation switches. Whether you are outfitting a commercial marine vessel, a dual-battery 4WD canopy, or an off-grid caravan power system, the 187-Series provides dependable thermal response to safeguard your wiring and high-draw appliances.
Engineered for Harsh Marine and Automotive Environments
Inferior circuit breakers often suffer from voltage drop, corrosion, and premature failure when exposed to vibration and moisture. The Blue Sea 187-Series overcomes these common failure points with a fully waterproof housing and robust internal components. Because it is ignition-protected, this breaker will not ignite surrounding flammable gases if a spark occurs internally, making it safe for installation inside the engine compartments of petrol-powered boats and near battery enclosures.
Safety is further enhanced by a trip-free internal mechanism. In the event of a dangerous short circuit or continuous overload, the breaker cannot be manually held in the closed position, preventing catastrophic wire overheating and equipment damage. The high-visibility yellow reset lever provides an immediate visual indication of the circuit status and can be installed vertically or horizontally to suit your layout.
Key Features and Benefits
- Combined Switching and Protection: Functions as both a precision thermal circuit breaker and a convenient manual battery or load disconnect switch.
- Trip-Free Safety Mechanism: Internal contacts cannot be forced closed during an active fault current condition, reducing fire risks.
- Ignition Protected: Safe for installation aboard petrol-powered boats and in enclosed compartments with potential vapour build-up.
- Heavy-Duty Connections: Features large 5/16" (Approx. M8) stainless steel stud terminals that accept high-torque connections and provide ample clearance for heavy-gauge cable lugs.
- Weatherproof Construction: Sealed body protects internal components against moisture, dust, and salt spray in exposed mounting locations.
- Clean Surface Installation: Recessed mounting holes allow for secure attachment on flat panels and bulkheads without exposed fastener heads.
Practical Installation and Application Notes
Designed for straightforward integration into heavy-duty wiring harnesses, the generous clearance around the 5/16" (Approx. M8) terminal studs makes fitting thick battery cables simple and secure. This 50A DC circuit breaker is suited for protecting auxiliary battery lines, windlasses, inverter feeds, and primary distribution panels up to 48V DC.
Application Exclusion: Do not use this thermal circuit breaker as a frequent manual switch where high inrush currents are expected, as repeated switching under heavy surge loads can degrade the internal contact surfaces over time.
Upgrade Your Electrical Safety
Protect your high-current DC investments with proven marine-grade hardware. Add the Blue Sea 187-Series 50A Surface Mount Thermal Circuit Breaker to your system today for safe, simplified circuit management.
SKU: BS-7139B
SPECIFICATIONS
| Specification | Details |
|---|---|
| Product type | Thermal circuit breaker |
| Mounting / form factor | Surface mount |
| Ignition Protected | Yes |
| Terminal Size | 5/16 (M8) |
| SKU: | BS-7139B |
| Model #: | BS-7139B |
| MPN: | BS-7139B |
| HS code: | 8536200040 |
| Country of origin: | MX |
| Package weight: | 0.42 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
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