Sea-Dog SD-87 40A Resettable Circuit Breaker 48V DC
Sea-Dog SD-87 40A Resettable Circuit Breaker 48V DC — Product description
The Sea-Dog SD-87 is a 40-amp resettable circuit breaker for marine DC circuits up to 48 volts. Manual reset means you clear a trip by hand instead of hunting for a spare fuse, and the IP66-sealed housing shrugs off spray. Surface mount with 5/16 inch-18 stud terminals, built to ABYC and UL standards.
The Sea-Dog SD-87 is a 40-amp resettable circuit breaker built for the kind of DC circuits you actually run on a boat. Bilge pumps, windlasses, electronics feeds, accessory panels, anything that pulls a steady load and needs protection close to the battery. It handles up to 48 volts DC, so it covers 12, 24, 36, and 48-volt systems without you having to think twice about it.
What sets a good breaker apart from a fuse is that you can bring it back to life. When this one trips, you flip it back with the manual reset. No digging through a spares box for the right fuse in a rolling anchorage. Find the fault, fix it, push the breaker back in, and you're running again. That alone makes it worth the money on any circuit you can't afford to lose while you're out there.
It's a surface-mount unit, so it bolts flat to a bulkhead, a panel, or the side of a battery box. The connections are 5/16 inch-18 stud terminals, which take a proper ring terminal and a lock washer and stay put through vibration and pounding. That's the connection you want on a windlass or thruster feed, not a push-on spade that works loose after a season.
Sea-Dog sealed this one to an IP66 rating, so wind-driven spray and washdown water won't find their way into the mechanism. The housing is black plastic and it's sized to sit in a machinery space or an exposed console without complaint. It meets SAE J553, ABYC E-11, UL1077, and SAE J1171, which is the paperwork surveyors and insurers like to see on a marine build.
A couple of things to keep in mind. This is the single-breaker version, so order one per circuit you're protecting. And it's a 40-amp unit, so size it to the wire and the load, not just whatever's on the shelf. Match the breaker to the smallest wire in the run and you'll be right. For a lot of mid-size accessory and pump circuits, 40 amps is the sweet spot.
Key Features
- 40 amp rating protects mid-size DC circuits like pumps, windlasses, and accessory feeds
- Rated to 48 volts DC, covers 12V, 24V, 36V, and 48V systems
- Manual reset button clears a trip by hand, no spare fuse to carry
- IP66-sealed housing keeps out wind-driven spray and washdown water
- 5/16 inch-18 stud terminals take ring terminals for a secure, vibration-proof connection
- Surface-mount design bolts flat to a bulkhead, panel, or battery box
- Meets SAE J553, ABYC E-11, UL1077, and SAE J1171 marine standards
Why Buy from NVN Marine
- Authorized Sea-Dog reseller, full manufacturer warranty
- NMEA member and ABYC certified, advice from real boat techs
- Same-day shipping before 3 PM ET on in-stock items
- NY headquarters and Fort Lauderdale flagship retail store
Technical specifications
| Title | SD-87 Resettable Circuit Breaker, 40 Amp, 48 Volt DC, Manual Reset, Surface Mount |
|---|---|
| Brand | Sea-Dog |
| Manufacturer Part Number | 830522 |
| UPC | 035514830669 |
| Series | SD-87 |
| Amperage | 40 Amp |
| Voltage | 48 Volt DC |
| Reset Type | Manual Reset |
| Mounting | Surface Mount |
| Terminal | 5/16 Inch-18 Stud Terminal |
| Color | Black |
| Material | Plastic |
| Protection Rating | IP66 |
| Standards | SAE J553, ABYC-E11, UL1077, SAE J1171 |
| Quantity | Single |
Frequently asked questions
What size circuit does the SD-87 protect?
It's a 40-amp breaker, so it's sized for mid-size DC circuits. Always match the breaker to the smallest wire in the run and the load it feeds.
Does it work on 12-volt and 24-volt systems?
Yes. It's rated up to 48 volts DC, which covers 12V, 24V, 36V, and 48V circuits.
Does the breaker reset itself after it trips?
No. It's a manual-reset breaker. When it trips you clear the fault and push the reset by hand, so there's no fuse to replace.
How does it mount?
It's a surface-mount unit that bolts flat to a bulkhead, panel, or battery box. Connections are 5/16 inch-18 stud terminals that take ring terminals.
Is it protected against water?
It carries an IP66 rating, so wind-driven spray and washdown water stay out of the mechanism.
Does it meet marine electrical standards?
Yes. It's built to SAE J553, ABYC E-11, UL1077, and SAE J1171.
