Blue Sea Systems ST Blade Fuse Block, ATO/ATC, 32V DC, Screw Terminal

Overview

The Blue Sea Systems ST Blade is a screw-terminal ATO/ATC fuse block range for organizing DC branch circuit protection on boats and other marine electrical systems. It is built for systems up to 32V DC, with configurations for 6 or 12 circuits, a maximum rating of 100A per block, and up to 30A per circuit when matched with the correct fuse and wire size.

This range helps clean up the common tangle of inline fuses behind helm stations, electronics panels, cabin panels, and accessory distribution areas. A single positive feed supplies the fuse block, then each protected branch circuit leaves from its own screw terminal for items such as electronics, pumps, lighting, instruments, and other low-voltage DC loads.

Versions are available with or without a negative bus and with or without a protective cover, so the layout can match the wiring space on board. Models with a negative bus give DC returns a dedicated landing point at the block, while covered versions add insulation over the live fuse area and include space for circuit labeling.

Key features

• Accepts standard ATO and ATC fast acting blade fuses for common marine DC branch circuits.
• Rated for up to 32V DC, with 100A maximum per block and 30A maximum per circuit when installed with proper wire and fuse sizing.
• Available in 6-circuit and 12-circuit layouts to suit smaller accessory groups or larger helm and house distribution runs.
• Positive distribution bus uses a #10-32 stud, giving the main feed a secure connection point.
• Negative bus versions use a #10-32 stud and help keep positive and negative branch wiring organized in one location.
• Tin-plated copper buses and fuse clips help maintain conductivity in the electrical system.
• Screw terminals accept ring or snap fork terminals, which are common choices for serviceable marine wiring.
• Cover-equipped versions satisfy ABYC and USCG insulation requirements, provide easier fuse access, store two spare fuses, and include label recesses for circuit identification.
• Fuses are sold separately, allowing each branch circuit to be fused to match the connected load and wire size.

Variants

This ST Blade range varies by circuit count, negative bus configuration, and whether a cover is included. The 6-circuit versions suit smaller accessory groups or compact wiring areas, while the 12-circuit versions reduce the need for multiple fuse blocks when more branch circuits are being added.

The negative bus versions are useful when the block will also serve as a local return point for DC loads. Cover-included versions add insulation, spare fuse storage, and label space, while uncovered versions may be selected for installations where a cover is not needed or where the block is being installed inside a protected enclosure.

Installation and setup

The fuse block mounts with #8 screws and uses #8-32 screw terminals with captive star lock washers for branch circuit connections. The screw terminal torque is 18 in-lb, and the main bus stud torque is 24 in-lb. Those torque values matter on boats, where vibration can loosen poorly secured electrical connections over time.

Install it in a dry, serviceable location that allows the cover to open when fitted and leaves enough room to route conductors without sharp bends. Each circuit should be labeled during installation, especially on helm, console, or cabin panels where future troubleshooting needs to be quick and clear.

Electrical use on board

This fuse block works well as a DC sub-panel for electronics and accessory circuits, especially when a main distribution panel is already crowded or when several small loads need nearby protection. It is a practical fit for console rewires, new electronics installs, bilge and utility circuits, lighting additions, and house-side accessory distribution.

Each branch circuit still needs the correct fuse rating for the connected load and wire gauge. For clean service work later, keep the main feed, branch conductors, and negative returns neatly supported, and avoid placing the block where it will be exposed to standing water or constant spray.

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Orders of $100 or more qualify for free shipping when eligible. For orders under $100, shipping costs are calculated at checkout based on destination, package weight, and selected service. International shipping is available for eligible products, and certain items may require additional handling, warehouse transfers, or may ship directly from the manufacturer, which can affect processing time.

Deliveries are handled by preferred carriers such as USPS, UPS, FedEx, DHL, and others depending on your location and selected service. Estimated delivery times are displayed at checkout and may vary due to customs processing, carrier delays, weather, postal disruptions, or other circumstances beyond our control. Once your order ships, you'll receive a confirmation email with tracking information. Tracking may take up to 24 hours to update on the carrier's website and is also available through your account when applicable.

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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