RT18 Filled Enclosed Tubular Fuse & Fuse Holder

RT18 10×38 Open Type Fuse Holder – A Reliable Sourcing Solution for A Low Voltage Protected Environment

Overcurrent and Short Circuit events to our Industrial Electrical Systems create an ongoing risk of damaging costly Electrical Equipment or Dangerous Electrical Fires. The HUYU Electric RT18 Fused Enclosed Holder produces an insulated and secure enclosure for any of the 10x38mm Cylinder Fuses. Therefore providing a Total Overcurrent Protection Point in your AC Operations up to 380v 32 amps. The filled enclosed design of the RT18 enables it to retain arc energy within the enclosure, preventing the dangerous transfer of energy to other components that may be in the same area or very busy Control Panels.

Designed to be mounted on a DIN Rail providing an easy snap-fit to engineered standard 35mm rails, therefore enabling rapid and tool free installation or replacement. The Flame Retardant Polymeric Material of the fuse holder housing meets the Fire Safety Standards of Modern Industrial Switchgears. Electrical Distributors and Panel Builders that require a reliable Industrial Fuse Holder for Motors, Control Circuits, and Power Distribution will find HUYU Electric is an OEM/ODM Factory Direct Supplier, providing full documentation of the product.

Technical Specifications

Reliable Circuit Protection for Industrial Applications

The cubic RT18 cylinder fuse holder is designed for the true needs of industrial controls and power distribution, and its construction is enclosed and filled. This means that not only do fuses need to work properly, but also that when the fuse operates, it generates heat and arcs which could potentially damage other devices on the DIN rail. If the individual elements were housed in non-enclosed space, using smaller public sizes of fuses and being spaced even more closely together could limit the amount of circuits able to be used within that restricted space, with each line taking up a minimum of 18mm in width. Replacement fuse links will be found anywhere in the world, as standard sizes of 10×38mm are being sold throughout the world to use as replacements for the fuses mentioned above, regardless of where the fuses may have been installed. For motor control centers, HVAC control panels, and industrial automation, the RT18 tubular fuse holders provide a very simple and effective means of protecting against overcurrent and are designed to fit into any configuration on the DIN rail.

OEM / ODM Supply – Industrial Slotted Tube Fuse Holders for Panel Builders

Buyer’s Guide

How to Select a Tubular Fuse Holder for Industrial Control

Key selection criteria for the RT18 in industrial power distribution and motor protection.

1. Correctly Sizing the Fuse Link

As a rule of thumb, the fuse current rating should equal the amount of current flowing through the load you are protecting. When protecting motors, fuse links must be sized to handle both the starting (inrush) current and provide enough protection for typical applications – usually 125-175% of full load depending upon the type of motor and its method for starting. RT18 tubular fuse holders accept standard 10x38mm fuse links which come in current ratings from 2-63A.

2. Filled Enclosed vs. Open Clip Tubular Fuse Holders

The filled enclosed design of the RT18 provides a significant safety benefit over open-clip tubular fuse holders. When an overcurrent condition occurs and the fuse operates in a high fault current, the arc energy is contained within the ceramic tube and holder enclosure — protecting terminals or components from an arc flash. In industrial control panels (where reliability and safety are primary concerns), the filled enclosed design is recommended.

3. Snap on DIN Rail Mounting

RT18 fuse holders mount onto standard 35mm DIN rails with no tools required. At only 18mm wide per pole, they fit neatly among circuit breakers, contactors, relays, and other devices using DIN rails, making them ideal for crowded industrial control panel with minimal available space.

4. Voltage/Current Ratings

Ensure that the 380VRMS rating of the RT18 fuse holder meets or exceeds the system’s operating voltage. RT18-32 can accept up to 32A fuse links; RT18-63 accepts up to 63A fuse links. Use the RT18 model that meets the maximum fuse link current required by the protected circuit.

Frequently Asked Questions

How does a fuse holder work?

A fuse holder works by providing a secure, insulated mounting point for a replaceable fuse link. It has two conductive clips or terminals that grip the metal end caps of the fuse, connecting it in series with the circuit. Under normal operation, current flows through the holder’s terminals, through the fuse element, and out to the load. When an overcurrent or short circuit occurs, the fuse link inside the holder melts and interrupts the current. The RT18 enclosed fuse holder contains the arc and heat generated during this interruption within its filled, flame-retardant housing, preventing damage to adjacent components. The DIN rail design allows quick snap-in installation and easy fuse replacement when needed.

How to connect fuse holder to wire?

To connect the RT18 tubular fuse holder to wire, first ensure the circuit is completely de-energized. Strip the wire ends to the appropriate length as specified in the product data sheet. Insert the stripped wire into the holder’s screw terminal — the RT18 features clearly marked input and output terminals. Tighten the terminal screw to the specified torque using an appropriate screwdriver. Connect the supply side (line) to one terminal and the load side to the other. After double-checking that the correct fuse link is inserted and all connections are secure, the circuit can be re-energized. For industrial installations, always follow local electrical codes and have the work performed or inspected by a qualified electrician.

How to connect inline fuse holder?

An inline fuse holder is spliced directly into a cable run. To connect one, first de-energize the circuit. Cut the cable at the desired location, strip the ends, and connect one side to each terminal of the inline holder. The RT18 is a DIN rail mount cylindrical fuse holder, not an inline type — it is designed for fixed installation in control panels rather than in-cable splicing. For panel-mounted applications, the RT18’s DIN rail design provides a more secure, professional installation than an inline holder, with the added safety of an enclosed, filled construction that contains arc energy when a fuse operates.

How to fix a broken fuse holder?

Fixing a broken fuse holder depends on the type of damage. If the fuse clips have lost tension, are corroded, or show signs of overheating (discoloration or deformation), the entire holder should be replaced — damaged clips can cause high resistance connections that lead to further overheating. If a terminal screw is stripped, replacement is also recommended. For the RT18 industrial fuse holder, replacement is straightforward: de-energize the circuit, remove the wiring from the terminals, unclip the old holder from the DIN rail, snap a new RT18 onto the rail, re-connect the wires, and insert the fuse link. Attempting to repair a damaged holder with adhesives or makeshift fixes is unsafe and violates electrical codes. Always replace a damaged fuse holder with a new, certified unit.