Blue Sea 300A Black Mini m-Series On/Off Battery Switch w/ Key
Blue Sea 300A Black Mini m-Series On/Off Battery Switch w/ Key
300A Continuous - Ignition Protected - Removable Key Security
Highlights:Rotary Knob: Ergonomic knob for switching between ON and OFF positions,Amperage Ratings: 300A continuous, 500A intermittent and 900A cranking ratings,Position Indicators: High-contrast OFF and ON labels for clear status identification,Mounting Points: Recessed mounting holes accepting #10 screws. 
DESCRIPTION
Blue Sea m-Series Mini: High-Amperage Battery Isolation with Security Key
Compact Power Management for Marine and RV Systems
The Blue Sea 300A Mini m-Series Battery Switch delivers professional-grade power isolation in a compact footprint, solving the challenge of limited installation space on modern boats, caravans, and 4WDs. Despite its small size, this switch is engineered to handle significant power loads, offering a continuous rating of 300A and a cranking rating of up to 900A. This makes it an ideal solution for managing main battery banks without the bulk associated with traditional heavy-duty switches.
Designed for versatility, this unit operates effectively across a wide voltage range. While the specifications list a maximum of 48V DC, it is perfectly suited for standard 12V and 24V systems commonly found in automotive and marine applications. This flexibility ensures it can accommodate future system upgrades, such as moving to higher voltage lithium banks, without needing replacement.
Enhanced Security with Removable Key
Unlike standard rotary switches, this model features a removable key mechanism. This function is critical for preventing unauthorised use of your vessel or vehicle, acting as an effective theft deterrent. Additionally, it serves as a safety lockout during maintenance, ensuring that the electrical system cannot be accidentally engaged while you are working on the engine or electrical circuits.
Ignition Protected for Safety
Safety is paramount in enclosed engine rooms and fuel storage areas. This switch is ignition protected, meaning it is safe for installation aboard gasoline-powered boats. The design prevents internal sparks from venting and potentially igniting surrounding fumes, complying with ISO 8846 and SAE J1171 standards. Whether you are outfitting a ski boat or a camper trailer, this feature provides peace of mind regarding fire safety.
Robust Construction and Installation
Built to withstand harsh Australian marine conditions, the switch features tinned copper studs for maximum conductivity and corrosion resistance. The 3/8"-16 (Approx. M10) stud terminals are designed to accept heavy-duty cable lugs up to 4/0 AWG (approx. 120mm²), ensuring you can use the appropriate cable gauge to minimise voltage drop.
Installation is simplified with a case design that allows for surface, front panel, or rear panel mounting. The included isolating cover with snap-on sections protects rear contacts, preventing accidental short circuits.
*Note typical de-rating factors apply to maximum current ratings.
- 300A continuous rating handles high-demand loads in a compact frame
- Removable key enhances security and allows for service lockout
- Ignition protected design is safe for use in petrol engine compartments
- Tinned copper terminals resist corrosion and ensure reliable power transfer
- Flexible mounting options suit surface or panel installations
- Compatible with 12V, 24V, and 48V electrical systems
Secure Your Electrical System Today
Upgrade your battery management system with a switch that prioritises safety and security. Order the Blue Sea m-Series Battery Switch with Key to ensure reliable isolation for your boat or touring vehicle.
SKU: BS-6005200B
SPECIFICATIONS
Specifications
| Switch Type | Single Circuit ON-OFF |
|---|---|
| Color | Black |
| Switch Positions | 2 |
| Battery Combine | No |
| Alternator Field Disconnect | No |
| Maximum Voltage | 48V DC |
| Stud Size |
3/8" (approx. 9.53 mm; reference only) |
| Terminal Stud Torque |
120 in-lb (13.56 N·m) (approx. 10.0 ft-lb; reference only) |
| Continuous Rating | 300A |
| Intermittent Rating | 500A (5 min) |
| Starting Rating (30 sec) | 900A |
| Battery Inputs | 1 |
| Cable Clearance For 4/0 AWG Cables |
1.12in (28.45 mm) (reference only) |
| Cable Size to Meet Ratings |
4/0 AWG (120mm²) (AWG vs mm² is an approximate equivalence; reference only) |
| Mounting Holes |
Accept #10 Screw (approx. #10 major diameter 4.83 mm; reference only) |
| Stud Material | Tinned Copper |
| Stud Torque |
120 in-lb (13.56 N·m) (approx. 10.0 ft-lb; reference only) |
| Switching Rating | 25A |
| Terminal Stud Size |
3/8" - 16 (M10) (3/8" ≈ 9.53 mm major diameter; M10 is 10 mm; 16 TPI ≈ 1.59 mm pitch; reference only) |
| Weight (min / max) |
0.62–0.62 lb (0.28–0.28 kg) (approx. 280 g; reference only) |
| SKU: | BS-6005200B |
| Model #: | BS-6005200B |
| MPN: | BS-6005200B |












































