Blue Sea Systems Class T Fuse Block with Insulating Cover, 160V DC

Overview

The Blue Sea Systems Class T Fuse Block with Insulating Cover is a high-current fuse holder range for Class T fuses on DC marine electrical systems up to 160V DC. It is made for fast-acting overcurrent protection in demanding circuits such as inverter feeds, large battery banks, chargers, and other high-load electronics where a short circuit needs to be interrupted quickly.

Across the range, the block accepts cable up to 4/0 AWG and uses tin-plated copper fuse mounting blocks to carry high current with low resistance. The insulating cover helps protect exposed conductors and satisfies ABYC and USCG insulation requirements, while cover breakouts let the installer route heavy cable from different directions without forcing an awkward bend.

This is a practical choice for boats where high-current wiring needs to stay serviceable after installation. The open stud layout gives room around large lugs, and the covered design suits battery compartments, inverter locations, and protected machinery spaces where vibration, heat, and accidental contact are real concerns.

Key features

• Supports Class T fuses for fast-acting circuit protection on high-current DC loads such as inverters and other onboard electronics.
• Rated for DC systems up to 160V, with variant fuse ranges covering 110 to 200A and 225 to 400A applications.
• Accepts cable up to 4/0 AWG, which helps with large battery and inverter cable runs common on cruising and power management systems.
• Insulating cover satisfies ABYC and USCG insulation requirements and helps reduce the risk of accidental contact with live terminals.
• Cover breakouts allow wire access from multiple directions, making the block easier to fit in tight electrical spaces.
• Tin-plated copper fuse mounting blocks help carry high current and resist corrosion in marine electrical environments.
• Four-stud layout gives installers room to land large cable lugs without crowding the fuse connection.

Variants

This product is offered in multiple Class T fuse block configurations for different fuse ranges, ignition protection requirements, and terminal stud sizes.

The main differences are the supported Class T fuse range, whether the block is ignition protected, and the terminal stud size used for the main cable connections. All listed configurations are for systems up to 160V DC and use an insulating cover.

• 5007100: Class T fuse range 110 to 200A, ignition protected, with 1/4"-20 terminal studs. This version suits lower high-current Class T fuse installations where ignition protection is required and the cable lugs match the smaller stud size.
• 5502100: Class T fuse range 225 to 400A, ignition protected, with 5/16"-18 terminal studs. This configuration is used for higher-current protected circuits that still require an ignition-protected fuse block.
• 5502: Class T fuse range 225 to 400A, not ignition protected, with 3/8"-16 terminal studs. This version fits high-current installations where ignition protection is not required and larger 3/8" ring terminals are being used.

Installation and fit

Match the selected block to the fuse amperage, terminal stud size, cable lug hole size, and the location where it will be mounted. For inverter and battery circuits, the fuse block should be installed as close to the power source as the system layout and applicable marine electrical practices allow.

Use properly crimped ring terminals that match the cable size and stud size. The cover should be fitted after connections are tightened so the terminals remain protected while still allowing service access when the fuse needs inspection or replacement.

Compatibility and system use

These blocks are for Class T fuses and should not be mixed with other fuse formats. They are well suited to high-current DC circuits on cruising boats, fishing boats, and larger power systems where inverter loads or large battery banks require fast short-circuit protection.

The ignition-protected variants are the correct style to consider for spaces where ignition protection is required by the installation. The non-ignition-protected 5502 is better matched to protected electrical areas where that rating is not needed.

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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