Blue Sea 600A HD-Series Heavy Duty On/Off Battery Switch w/ AFD
Blue Sea 600A HD-Series Heavy Duty On/Off Battery Switch w/ AFD
600A Continuous - Alternator Field Disconnect - 1/2" (M12) Studs
Key features: Continuous rating of 600A and intermittent 900A, Ignition protected for safe marine installation, Single circuit ON-OFF operation, Max voltage 32V DC.
Highlights:Input Stud: 1/2 inch (M12) tinned copper stud for battery input,Output Studs: Dual studs to accommodate multiple load cables,AFD Terminals: Connections for Alternator Field Disconnect,Mounting Hole: Accepts 1/4 inch (M6) screws for secure installation.
Technical diagram showing two mounting options: standard surface mount or panel mount requiring a 3-5/8 inch diameter hole cutout. 
DESCRIPTION
Blue Sea Systems HD-Series: High-Current Battery Isolation with AFD
Reliable Power Management for 12V and 24V Systems
The Blue Sea 600A HD-Series Battery Switch is engineered for high-demand electrical systems found in large marine vessels, RVs, and off-grid setups. Designed to manage high-amperage battery banks, this switch allows you to toggle a single battery bank to a single load group with confidence. Its ignition-protected design makes it safe for installation in gasoline engine rooms, while the robust construction ensures longevity in harsh marine and automotive environments.
Protect Your Charging System with AFD
A key feature of this model is the Alternator Field Disconnect (AFD). In the event the battery switch is accidentally turned to the 'OFF' position while the engine is running, the AFD interrupts the alternator field current before the main circuit is broken. This prevents voltage spikes that can destroy the diodes in your alternator, saving you from costly repairs and electrical downtime compared to standard isolation switches.
Built for Heavy-Duty Applications
Capable of handling continuous loads of 600A (when wired with adequate cabling), this switch is ideal for diesel engines and systems with significant power draws. The 1/2" (approx. M12) tinned copper studs provide maximum conductivity and corrosion resistance, accepting large battery cables equipped with heavy-duty lugs. The versatile case design offers flexibility, supporting both surface mounting and rear panel installation to suit your specific layout.
- High Current Rating: Handles 600A continuous and 1750A cranking (30 sec), ideal for heavy diesel starting loads.
- Alternator Protection: Integrated AFD safeguards your alternator diodes during accidental switching.
- Ignition Protected: Safe for use on gasoline-powered boats and within engine compartments (SAE J1171).
- Flexible Connection: Accepts two 4/0 AWG (approx. 120mm²) cables per terminal to meet maximum current ratings.
- Versatile Mounting: Fits standard panel cutouts or surface mounts with 1/4" (approx. M6) hardware.
Applications and Compatibility
This master battery switch is perfectly suited for managing main power in boats, camper trailers, and 4x4 setups running 12V or 24V systems (Rated up to 32V DC). Whether you are upgrading your marine electrical system or building a robust dual-battery setup for an RV, the HD-Series provides the safety and reliability required for professional-grade installations.
Secure your electrical system today. Equip your vessel or vehicle with the Blue Sea HD-Series Switch for safe, heavy-duty isolation.
SKU: BS-3001B
SPECIFICATIONS
Specifications
| Switch Type | Single Circuit ON-OFF |
|---|---|
| Color | Grey |
| Switch Positions | 2 |
| Battery Combine | No |
| Alternator Field Disconnect | Yes |
| Maximum Voltage | 32V DC |
| Terminal Stud Torque |
220 in-lb (24.86 N·m) (approx. 18.3 ft-lb; reference only) |
| Continuous Rating | 500A |
| Intermittent Rating | 900A (5 min) |
| Starting Rating (30 sec) | 1750A |
| Battery Inputs | 1 |
| Cable Clearance For 4/0 AWG Cables |
1.10in (27.94 mm) (reference only) |
| Cable Quantity to Meet Ratings | Two Cables |
| 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 |
1/2" (M12) (1/2" ≈ 12.70 mm; M12 is 12 mm; reference only) |
| Weight (min / max) |
1.30–1.30 lb (0.59–0.59 kg) (approx. 590 g; reference only) |
| SKU: | BS-3001B |
| Model #: | BS-3001B |
| MPN: | BS-3001B |














































