Product Overview
This high-capacity fuse relay box is designed to provide a complete circuit solution for various electrical systems, primarily in automotive, bus, tanker, boat, yacht, and ship applications. It features two slots for 5-pin relays and an eight-slot ATC/ATO fuse holder, offering ample space for your electrical needs. Constructed from premium, high-temperature resistant materials, this unit is robust and will not deform under extreme heat, ensuring reliable performance.

Figure 1: A detailed view of the fuse relay box, showcasing its compact design and the arrangement of relay and fuse compartments.
Setup and Installation
The fuse relay box is engineered for easy and secure installation. Its unique single-rail design allows it to be mounted conveniently in various locations within your vehicle or vessel. This design also facilitates quick maintenance and replacement of relays and fuses.
Installation Steps:
- Identify a suitable mounting location: Choose a dry, secure area away from excessive vibration and direct heat sources, ensuring adequate space for wiring and future access.
- Secure the relay box: Utilize the integrated mounting points or the unique rail system to firmly attach the box to the chosen surface.
- Wire the circuits: Connect your electrical circuits to the appropriate fuse and relay terminals. Ensure all connections are secure and properly insulated. Refer to your vehicle's or system's wiring diagram for correct circuit integration.
- Insert relays and fuses: Once wiring is complete, insert the provided 5-pin relays into their designated slots and the ATC/ATO blade fuses into their respective holders.


Figure 2: The fuse relay box shown in an automotive environment (RV and car engine bay), highlighting its suitability for various vehicle types due to its unique track installation design.
Operating Principles
The fuse relay box functions as a central distribution point for electrical power, protecting circuits from overcurrents and enabling the control of high-current devices using low-current signals. Fuses provide overcurrent protection by melting and breaking the circuit if the current exceeds a safe level. Relays act as electrically operated switches, allowing a small current to control a much larger current, which is essential for components like headlights, fuel pumps, or cooling fans.

Figure 3: A view of the fuse relay box connected to various electrical wires, illustrating how it manages and distributes power within a circuit.
Maintenance
Regular inspection and timely replacement of components are crucial for the longevity and reliable operation of your electrical system. The design of this fuse relay box allows for quick and easy access to both fuses and relays for maintenance.
Fuse Replacement:
- Identify a blown fuse: A blown fuse typically has a broken filament visible through its clear casing.
- Disconnect power: Always disconnect the power source to the circuit before attempting to replace a fuse.
- Remove the old fuse: Gently pull the blown fuse straight out of its slot.
- Insert a new fuse: Replace it with a new fuse of the exact same amperage rating. Using a fuse with a higher rating can lead to circuit damage or fire.
Relay Replacement:
- Disconnect power: Ensure the power to the relay circuit is off.
- Remove the old relay: Pull the faulty relay straight out of its socket.
- Insert a new relay: Push the new 5-pin relay firmly into the socket, ensuring all pins align correctly.

Figure 4: An exploded view of the fuse relay box components, showing the two 5-pin relays, various ATC/ATO fuses, and the included terminals, facilitating easy identification for replacement.
Troubleshooting
If a circuit connected to the fuse relay box is not functioning, follow these basic troubleshooting steps:
- Check the fuse: Inspect the fuse associated with the non-functioning circuit. If the filament is broken, replace it with a new fuse of the correct amperage.
- Test the relay: If the fuse is intact, the relay might be faulty. You can test a relay using a multimeter or by temporarily swapping it with a known good relay from a non-critical circuit (of the same type).
- Inspect wiring: Check all wiring connections to and from the fuse relay box for looseness, corrosion, or damage. Ensure all terminals are securely crimped.
- Verify power supply: Confirm that the fuse relay box is receiving adequate power from the vehicle's or system's power source.
If issues persist after these steps, it is recommended to consult a qualified automotive electrician or technician.
Specifications
| Feature | Detail |
|---|---|
| Product Type | Fuse Relay Box |
| Material | ABS (High-temperature resistant) |
| Relay Specifications | 12V DC, 30A, 5-pin (x2 included) |
| Fuse Type | ATC/ATO Blade Fuses (8 slots) |
| Included Fuses | 5A x 2, 10A x 3, 20A x 1 |
| Dimensions (Approx.) | 72mm (L) x 36mm (W) x 40mm (H) / 2.83in x 1.42in x 1.57in |
| Package Weight | Approx. 103 grams |
| Model Number | Cryfoktave9iwd6m4 |
| Country of Origin | China |

Figure 5: A technical diagram indicating the precise measurements of the fuse relay box, including its length, width, and height, for installation planning.
Package Contents
The complete package includes the following items:
- 1 x Fuse Relay Box
- 2 x 12V DC 30A 5-pin Relays
- 6 x ATC/ATO Blade Fuses (2x 5A, 3x 10A, 1x 20A)
- 13 x Fuse Terminals (quantity may vary slightly)

Figure 6: A comprehensive display of all items included in the package: the fuse relay box, two 12V 30A 5-pin relays, six assorted ATC/ATO fuses, and a set of terminals.
Warranty and Support
For information regarding product warranty, returns, or technical support, please refer to the purchase documentation or contact the seller directly. Ensure you have your product model number (Cryfoktave9iwd6m4) and purchase details available when seeking assistance.