Attwood Marine S3 Series Automatic Bilge Switch, 12V, 15A, Electronic Sensing

Overview

The Attwood Marine 4801-7 is a 12V automatic bilge switch that uses electronic sensing to activate a bilge pump when water reaches the switch and shut the pump off once the water is cleared. It is rated for pump loads up to 15 amps and comes with a 36 inch wire lead, so it fits many 12V bilge pump circuits where you want automatic operation without relying on a mechanical float switch.

This is the switch only, not the pump. Because it uses solid-state sensing and has no moving parts, it avoids the sticking and wear that can show up with float-style switches over time. The sealed electronics, chemical-resistant housing, and stainless steel components make sense in bilge spaces where water, foam, sludge, and fuel or oil residue are part of real use on board.

Mounting is flexible enough for tight bilge layouts. The switch can be installed on the bilge floor, on a stringer wall, or alongside a compatible pump basket, which helps when you are replacing an older switch and want to keep the sensing point low in the hull.

Key features

• 12V automatic bilge switch for pump circuits up to 15 amps
• Electronic sensing reads bilge water and helps reduce nuisance cycling from sloshing water, foam, and residue in the bilge
• No moving parts, so there is nothing to jam, crack, or wear like a mechanical float mechanism
• Sealed electronics with a chemical-resistant housing and stainless steel components
• 36 inch wire lead for routing in common bilge installations
• Mounts on the bilge floor, on a stringer wall, or alongside a compatible pump basket without extra brackets
• Backed by a 5 year warranty

Installation and setup

On a 12V boat, the main fit check is pump current draw. This switch is built for pumps that stay within the 15 amp limit, so it is important to confirm the pump load before wiring it into an automatic bilge circuit. The 36 inch lead gives enough reach for many compact bilge compartments without forcing splices right at the switch body.

The mounting choices are useful when the lowest part of the bilge is narrow or crowded. Keeping the switch in a spot where water collects naturally will help it respond as intended, while wall or basket mounting can make service access easier on boats where the bilge floor is hard to reach.

Compatibility and fit

This switch is a good match for owners replacing a worn float switch or adding automatic control to a compatible 12V bilge pump. It also works well where the bilge sees motion, foam, or dirty water that can make some mechanical switches cycle more often than they should. If your boat uses a 24V bilge circuit or a pump that pulls more than 15 amps, this is not the right version.

Use on board

This suits boats that spend time at the dock, on a mooring, or on a trailer between trips and still need the bilge protected automatically. It also makes sense for owners who want a cleaner switch setup in the bilge with fewer moving parts to service over time.

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We ship throughout the United States and to most international destinations for products eligible for international shipping. International orders may be subject to customs duties, taxes, brokerage charges, or other import fees, which are the customer's responsibility and are not included in the product or shipping price. PO Boxes are accepted only when shipping through USPS, and not all packages qualify for this option. If your order does not arrive within the estimated delivery window, please contact us at info@apollolighting.com or +1 (954) 375-0100 so we can assist with locating your package.

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Returns may be requested within 30 days of receiving your order. Items must be unused, uninstalled, unaltered, and returned in their original packaging with all tags, packing materials, blank warranty cards, manuals, instructions, accessories, and included items. Certain products, including installed or used electronics, electrical components, lighting, consumables, custom or special-order items, cut-to-length products, safety equipment, and merchandise exposed to water or marine conditions, may not be eligible for return.

To request a return, sign in to your account and select the applicable order and items, and submit your request for review. Eligible unfulfilled items may also be submitted for cancellation within 1 hour of placing the order. Returns or cancellations are not considered approved until you receive confirmation from Apollo Lighting. Please do not ship or drop off merchandise before receiving return approval and instructions.

Customers are responsible for arranging and paying for return shipping unless the return is due to an error by Apollo Lighting or the item is verified as defective, damaged, or incorrect. Missing, damaged, defective, or incorrect items must be reported within 2 business days of delivery, and photos or other documentation may be required for review. If the issue is verified, Apollo Lighting may provide or reimburse return shipping and issue a replacement or refund depending on the circumstances. International customers are responsible for return shipping, duties, taxes, customs charges, brokerage fees, and other costs associated with an international return.

After your return is received and inspected, approved refunds are issued to the original payment method and may take 5-7 business days to appear after processing. Original shipping and handling charges are nonrefundable, and the value of any included free items that are not returned may be deducted from the refund. Apollo Lighting does not charge a standard restocking fee on eligible returns. Returns that are incomplete, damaged, installed, used, altered, improperly packaged, or otherwise do not meet the eligibility requirements may be refused. We recommend using a trackable and appropriately insured shipping service for all customer-arranged returns.

For assistance, contact info@apollolighting.com or call +1 (954) 375-0100.

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Many products sold by Apollo Lighting include a manufacturer's warranty covering defects in materials or workmanship. Warranty terms vary by brand, product category, and model, so eligibility, coverage duration, exclusions, and available remedies are determined by the applicable manufacturer. We recommend reviewing the warranty information provided with your product before installation or use, especially for marine electronics, navigation equipment, lighting, electrical systems, pumps, safety equipment, and other specialized marine products.

If you need warranty service, the claim must follow the process established by the manufacturer, authorized service center, or designated warranty provider. You may be asked for proof of purchase, a serial number, product registration, photos, maintenance or installation records, or other documentation. Apollo Lighting does not determine or modify a manufacturer's warranty coverage or final claim decision, but we are happy to help provide purchase information and direct you to the appropriate manufacturer or warranty resource.

Keep your receipt, product documentation, serial number information, and original packaging when practical. Damage caused by normal wear, misuse, improper installation, insufficient maintenance, corrosion, impact, unauthorized modifications, electrical issues, or operation outside the manufacturer's specifications may not be covered. Warranty claims are separate from standard returns, so a product that has been installed, used, or exposed to marine conditions may no longer qualify for return while still remaining eligible for evaluation under the manufacturer's applicable warranty.

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