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Blue Sea 300A Black Mini m-Series 4 Position (OFF/1/2/1+2) Battery Selector Switch
Blue Sea 300A Black Mini m-Series 4 Position (OFF/1/2/1+2) Battery Selector Switch
Selects Battery 1, 2 or Both - 300A Continuous - Ignition Protected
Key features: Selects between Battery 1, Battery 2, or both (1+2), Ignition protected for safe marine installation, Compact m-Series design fits limited spaces, 300A continuous rating for reliable power management.
Highlights:Output Terminal: Connects to the engine or distribution panel,Battery 1 Input: Connection point for the positive terminal of Battery 1,Battery 2 Input: Connection point for the positive terminal of Battery 2,Mounting Hole: Accepts #10 screws for secure installation.
Versatile mounting options include surface, front panel, or rear panel installation to suit various enclosure depths and aesthetic requirements.
High-visibility rotary dial with distinct click-stops for OFF, 1, 2, and 1+2 positions, clearly displaying continuous and intermittent amperage ratings.
Schematic illustrating a typical two-battery bank installation, allowing isolation of starting and house circuits or combining them for emergency starting. 
Regular price
$72.00
Availability:
In Stock
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DESCRIPTION
Compact High-Current Battery Selection for Dual Bank Systems
The Blue Sea m-Series Battery Switch offers a professional solution for managing two isolated battery banks in marine, RV, and automotive applications. As a 4-position selector switch, it allows you to draw power from Battery 1, Battery 2, or both simultaneously, while also providing a complete disconnect (OFF) for safety and storage. Engineered for systems requiring high power handling in a small footprint, this switch is ideal for switching battery banks to all loads or combining them for emergency starting.
Whether you are outfitting a small boat with an outboard motor, setting up a dual battery system in a 4WD, or managing power in a camper trailer, the m-Series provides the reliability needed for critical electrical connections. Its compact design solves the problem of limited mounting space without compromising on amperage capacity.
Complete Control Over Two Battery Banks
This selector battery switch simplifies power management by allowing you to choose which battery bank powers your engine or house loads. The "1+2" position combines both banks, effectively paralleling them to provide extra cranking amps during emergency starting situations or to charge both banks simultaneously from a single charging source. This flexibility is essential for ensuring you always have a backup power source available if your primary starting battery is depleted.
Safe Switching with Make-Before-Break Technology
Protecting your vehicle's sensitive electronics and charging components is paramount. This unit features a make-before-break contact design, which allows you to switch between battery banks (e.g., from 1 to 2) while the engine is running without interrupting power flow. This feature prevents potentially damaging voltage spikes that can harm alternators and sensitive navigation or communication equipment, ensuring seamless operation during use.
High-Current Performance and Compatibility
Despite its mini form factor, the m-Series is built to handle significant electrical loads. It is rated for 300A continuous current, making it suitable for most marine and automotive DC circuits up to 32V. For short bursts, such as engine cranking, it can withstand up to 900A for 30 seconds. The switch utilises 3/8"-16 (approx. M10) tinned copper studs that provide maximum conductivity and corrosion resistance. These terminals are capable of accepting heavy-duty ring terminals and cables up to 4/0 AWG (approx. 120mm²), ensuring minimal voltage drop even in high-demand setups.
Flexible Installation Options
Installation in tight spaces is made easier with versatile mounting configurations. The switch can be surface mounted, front panel mounted, or rear panel mounted, accommodating various dashboard and locker layouts. It fits standard mounting holes (accepts #10 screws or approx. M5) and includes a snap-on rear cover to insulate terminals, adding an extra layer of safety against accidental short circuits.
- 4-Position Selector: OFF, 1, 2, and 1+2 for versatile battery management
- High Current Rating: 300A continuous, 500A intermittent (5 min), 900A cranking (30 sec)
- Ignition Protected: Safe for installation aboard petrol-powered boats
- Make-Before-Break: Safely switch between banks without stopping power flow
- Heavy-Duty Terminals: 3/8"-16 (approx. M10) studs accept up to 4/0 AWG (approx. 120mm²) cables
- Water Resistant: IP66 rating ensures durability in damp marine environments
Reliable Power Management for Your Next Adventure
Ensure your electrical system is safe, efficient, and versatile with the Blue Sea m-Series Battery Switch. Whether you need to isolate a starting battery or combine banks for a jump start, this switch delivers professional-grade performance.
Secure your power system today with this industry-leading battery selector switch.
SPECIFICATIONS
Specifications
| Switch Type | Selector 4 Position |
|---|---|
| Color | Black |
| Switch Positions | 4 |
| Battery Combine | Yes |
| Alternator Field Disconnect | No |
| Maximum Voltage | 32V 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 | 2 |
| 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) |
0.77–0.77 lb (0.35–0.35 kg) (approx. 350 g; reference only) |
| SKU: | BS-6007200B |
| Model #: | BS-6007200B |
| MPN: | BS-6007200B |
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.
