SparkFun Fuse Breakout Kit

The SparkFun Fuse Breakout Kit comes with everything you need to assembly & use a glass capsule, inline fuse (ferrule type) for your project. The simple breakout design allows for a barrel jack and the option for a screw terminal to be used for (VIN) power input and a second screw terminal used for VOUT. Any 5mm x 20mm glass capsule fuse can be used with this kit depending on your project needs but we have been sure to include a 250VAC, 500mA one to get you started. Make sure to check out the related products and add additional fuse in your cart as a replacement for prototyping and testing.

Fuses are pretty simple, if current exceeds the rating of the fuse, the small filament inside the fuse heats up and breaks (like a light bulb burning out). The circuit is then broken and hopefully, your circuit is saved from molten destruction. For smaller loads, you may want to check out a PTC (aka resettable fuse). Depending on the PTC's spec, they can handle less current (500mA) but can be set and reset many times without doing harm to your system. Since this is a kit, some soldering and assembly will be required.

  • 1x Fuse Breakout PCB
  • 2x 5mm pitch, 2 - pin screw terminals
  • 1x Glass Ferrule Fuse (5mm x 20mm) 250VAC, 500mA
  • 2x PTH fuse clips for 5mm diameter fuse
  • 1x PTH Barrel Jack connector

SparkFun Fuse Breakout Kit Product Help and Resources

Fuse Breakout Board Hookup Guide

October 3, 2019

Protect your project by adding a fuse in your circuit to save it from molten destruction.

Core Skill: Soldering

This skill defines how difficult the soldering is on a particular product. It might be a couple simple solder joints, or require special reflow tools.

1 Soldering

Skill Level: Noob - Some basic soldering is required, but it is limited to a just a few pins, basic through-hole soldering, and couple (if any) polarized components. A basic soldering iron is all you should need.
See all skill levels

Core Skill: DIY

Whether it's for assembling a kit, hacking an enclosure, or creating your own parts; the DIY skill is all about knowing how to use tools and the techniques associated with them.


Skill Level: Noob - Basic assembly is required. You may need to provide your own basic tools like a screwdriver, hammer or scissors. Power tools or custom parts are not required. Instructions will be included and easy to follow. Sewing may be required, but only with included patterns.
See all skill levels

Core Skill: Electrical Prototyping

If it requires power, you need to know how much, what all the pins do, and how to hook it up. You may need to reference datasheets, schematics, and know the ins and outs of electronics.

3 Electrical Prototyping

Skill Level: Competent - You will be required to reference a datasheet or schematic to know how to use a component. Your knowledge of a datasheet will only require basic features like power requirements, pinouts, or communications type. Also, you may need a power supply that?s greater than 12V or more than 1A worth of current.
See all skill levels


Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • Chiel / about 5 years ago / 1

    Dissapointing design. AC fuses should generally not be used in DC purposes as AC fuses are prone to be slow and leave small gaps that may result in Arcing. compared to DC fuses that are designed to be very fast and leave large gaps (often having a spring to pull the contact away on break). A DC fuse i would trust to break a higher DC voltage (~50v). An AC fuse i would not.

    If one wants to protect DC reliably one should be looking at DC-rated Fuses such as Multimeter fuses. They tend to be bulkier and more expensive than generic AC fuses, but will reliably break DC up.

    I know it ain't cheap and it can be very tempting to just assume an AC fuse will get the job done which it probably will, but it can't truly guarantee safety and is improper engineering.

  • Patronics / about 5 years ago / 1

    Would the holes for mounting the barrel jack connector happen to fit an XT60 connector like the ones you sell? Also what current level can this board tolerate? I'd like to use it with a 10A PTC fuse if possible.

    • I have not tried it with the XT60 connector but I doubt that the connector would fit into the screw terminal's PTH pads. The connector pins of the XT60 are bigger than the 5mm screw terminals.

      There are two polygons on the top layer of the breakout for +V that are pretty big but I have not calculated the maximum amperage through the polygon traces. I have only tested it up to 5A with the fuses available at SparkFun. Let me get back to you on that.

  • SK_BG / about 5 years ago / 1

    Sparkfun: Designs a PCB for DC power, adds warnings not to use it with AC, is sure to include a 250VAC fuse in the kit. :not-like-this:

    • CF / about 5 years ago / 4

      Pretty much any 5x20mm fuse you can find is rated for 250VAC. They work just fine on DC though.

      • Member #225064 / about 5 years ago / 1

        Please, for the safety of people who look to Sparkfun for sound reference designs, this kit should not be sold as a DC fuse when the socket is for an AC fuse (as pointed out above the kit even inculdes an AC fuse!). This may be a little known fact but it is worth pointing out here: it is not safe to use an AC fuse to protect for DC over current. Instead a DC rated fuse must be used for DC. A common form facor for a DC rated fuse is the blade style fuse commonly used in automotive.

        • Member #394180 / about 5 years ago * / 2

          This is only an issue when the voltage is high enough to maintain an arc after the fuse blows (since DC never crosses 0 volts). That's typically in the hundreds to thousands of volts range for an air-filed tube, even with some metal vapor from the blown fuse. For a 3.3 volt power supply it will simply never happen.

          • Member #225064 / about 5 years ago / 2

            An arc can be sustained at around 50V for a 9.5mm gap (see "DC-Arc Models and Incident-Energy Calculations" published in IEEE). Even for a "low" voltage system, higher transient voltage across a gap can be created if there is sufficient inductance (VL = L dI/dt) and this will be enough to initiate an arc. But I agree, a sustained arc is less likely or impossible when the DC voltage is low enough. Just be aware that DC systems above some minimum voltage (perhaps 40V?) are not properly protected by a fuse with only an AC voltage rating.

        • We've used glass cartridge fuses before in previous kits for DC applications. I'll see if I can bring this up for consideration but the fuses worked as expected for users.

Customer Reviews

5 out of 5

Based on 1 ratings:

Currently viewing all customer reviews.

Does the job

Easy way to protect circuit.