What’s the difference between marine wire and regular wire?

Marine wire uses tinned (tin-coated) copper strands that resist the corrosion salt air causes, and it’s more finely stranded so it flexes with vibration without breaking. Standard automotive or household wire corrodes and fails much faster in a marine environment.

How do I size a fuse for a marine circuit?

Size the fuse to protect the wire, not just the device. Match the fuse rating to the wire gauge’s safe current capacity so the fuse blows before the wire overheats. When adding a new circuit, follow the wire manufacturer’s ampacity chart for the gauge and run length you’re using.

Do I need a battery switch on my boat?

A marine battery switch is strongly recommended. It lets you disconnect the battery for storage or service, isolate a failed battery, and — on multi-battery setups — choose which bank powers the boat. It’s a core safety and reliability component.

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Perko

Perko Medium Duty Battery Selector Switch - 250A Continuous

Manufacturer: PerkoPart #: 8501DPSKU: 55851

250A
32V

$102.81Ships when available

Item #: 55851

Category: Battery Management

Currently out of stock. This item isn't available to order right now — check back soon or contact us for availability.

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Description

Medium Duty Battery Selector Switch - 250A Continuous Features: For use with 6 to 32 Volt Marine Electrical Systems Capacity - 250 AMPS Continuous, 360 AMPS Intermittent When used with Non-Unitized Alternators, these models will interrupt the field current (reducing the possibility of damage) if turned "OFF" with the engine running Specs: Diameter: 5-1/4" Depth: 2-5/8"

Specifications

Brand	Perko
Part Number	8501DP
EverTide SKU	55851
UPC	085226559471
Voltage	32 V

Specifications are provided by the manufacturer. Confirm fitment for your application before ordering, or contact us and we'll help.

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	Perko Medium Duty Battery Selector Switch - 250A Continuous$102.81You're viewing	Perko 8503DP Medium Duty Battery Selector Switch w/Alternator Field Disconnect w/o Key Lock$123.70	Perko 8504DP Medium Duty Battery Selector Switch w/Alternator Field Disconnect & Key Lock$142.53	Perko 9611DP Compact Medium Duty Main Battery Disconnect Switch$98.94
Voltage	32 V	32 V	32 V	32 V

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Perko 9611DP Compact Medium Duty Main Battery Disconnect Switch

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Returns & warranty

Returns are accepted within 30 dayson items that are unused and in their original packaging. Some items may be subject to a manufacturer restocking fee. Special-order items may not be eligible — if you're unsure, ask us before ordering.

Perko productscarry the manufacturer's standard warranty. For a warranty claim or a return authorization, see our full returns policy or contact us.

Electrical — frequently asked

What’s the difference between marine wire and regular wire?: Marine wire uses tinned (tin-coated) copper strands that resist the corrosion salt air causes, and it’s more finely stranded so it flexes with vibration without breaking. Standard automotive or household wire corrodes and fails much faster in a marine environment.
How do I size a fuse for a marine circuit?: Size the fuse to protect the wire, not just the device. Match the fuse rating to the wire gauge’s safe current capacity so the fuse blows before the wire overheats. When adding a new circuit, follow the wire manufacturer’s ampacity chart for the gauge and run length you’re using.
Do I need a battery switch on my boat?: A marine battery switch is strongly recommended. It lets you disconnect the battery for storage or service, isolate a failed battery, and — on multi-battery setups — choose which bank powers the boat. It’s a core safety and reliability component.

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