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Blue Sea 350A Red e-Series On Off Battery Switch
Blue Sea 350A Red e-Series On Off Battery Switch
Ignition protected, flexible mounting, marine-grade isolation
Key features: Ignition protected for marine environments, 350A continuous rating, Single circuit ON-OFF operation, Max 48V DC voltage.
Highlights:Terminal Studs: 3/8 inch (M10) tinned copper studs for maximum conductivity,Mounting Holes: Accepts 1/4 inch (M6) screws for secure installation,Amperage Ratings: Clearly marked high amperage ratings.
Two mounting options available: Panel mount into a 3-5/8 inch hole or Surface mount. 
Regular price
$81.00
Availability:
In Stock
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DESCRIPTION
High-current battery isolation for safer marine power systems
The Blue Sea e-Series ON/OFF battery switch is designed to give you confident control over a single battery feeding a single load group—ideal when you want a clear, manual way to isolate power for servicing, storage, or fault finding. In marine electrical systems, a dedicated battery isolator helps reduce the risk of accidental short circuits, parasitic drain, and unintended battery discharge when the vessel is unattended.
Built for demanding marine environments, this switch suits common Australian boating and 4WD auxiliary power setups where reliability and straightforward operation matter. Use it to quickly cut power to a house circuit, isolate a battery before maintenance, or create a simple, easy-to-understand system layout that technicians and owners can diagnose without guesswork.
Designed for marine installation requirements
This model is ignition protected, making it appropriate for installation on gasoline-powered boats where equipment may be exposed to fuel vapours. That extra layer of safety consideration can be important when upgrading older wiring or bringing a DIY install closer to accepted marine practices.
The e-Series housing also supports flexible installation, with a case design that allows either surface mounting or rear panel mounting. That means you can achieve a cleaner helm or switch panel finish, or mount it where cable routing is most practical—helpful when working with tight compartments and heavier battery cabling.
When this ON/OFF switch is the right choice
If your system is a single battery supplying a single circuit group, an ON/OFF battery switch is often the most direct option. It’s well suited to:
- Small to mid-size boats running a dedicated house battery
- Runabouts and fishing boats needing a simple battery cut-off for storage
- Auxiliary battery isolation in 4WDs, camper trailers, and portable power bays
- Workshop or test-bench DC systems where quick isolation improves safety during changes
Key features
- Single-circuit ON/OFF control to isolate one battery from one load group
- Ignition protected for use on gasoline-powered boats where vapour safety is a consideration
- Flexible mounting options with surface or rear panel mounting to suit your layout
- High-current capability suited to demanding DC loads common in marine and automotive auxiliary systems
- Clear manual isolation to support maintenance, storage, and fault diagnosis workflows
Why it helps in real-world installations
A robust battery switch can reduce common electrical issues such as slow battery drain from standby loads, hard-to-trace intermittent faults, and unsafe service conditions where circuits remain energised. By adding a dedicated isolation point, you can simplify troubleshooting and help protect sensitive electronics during maintenance or system changes.
For installers and DIY owners alike, the value is in predictability: a clear OFF position when you need the system de-energised, and a direct ON position when you’re ready to run. Pair it with appropriately sized cabling, correct terminal torque, and suitable circuit protection to support long-term reliability in harsh marine conditions.
SPECIFICATIONS
Specifications
| Switch Type | Single Circuit ON-OFF |
|---|---|
| Color | Red |
| Switch Positions | 2 |
| Battery Combine | No |
| Alternator Field Disconnect | No |
| Maximum Voltage | 48V DC |
| Terminal Stud Torque |
140 in-lb (15.82 N·m) (approx. 11.7 ft-lb; reference only) |
| Continuous Rating | 350A |
| Intermittent Rating | 600A (5 min) |
| Starting Rating (30 sec) | 1200A |
| Battery Inputs | 1 |
| Cable Clearance For 4/0 AWG Cables |
1.10in (27.94 mm) (reference only) |
| Cable Size to Meet Ratings |
4/0 AWG (120mm²) (AWG vs mm² is an approximate equivalence; reference only) |
| Mounting Holes |
Accept 1/4" (M6) Screw (1/4" ≈ 6.35 mm; M6 is 6 mm; reference only) |
| Stud Material | Tinned Copper |
| 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) |
0.95–1.30 lb (0.43–0.59 kg) (approx. 430–590 g; reference only) |
| SKU: | BS-9003EB |
| Barcode: | 632085900359 |
| Model #: | BS-9003EB |
| MPN: | BS-9003EB |
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.
