How to Test a Ceramic Fuse


Ceramic fuses act as a safety device that interrupts the electrical power supply when electrical overloads or surges occur. Internal, thin, wire filaments melt and stop the electrical current to prevent harm to an appliance or other electrical device. A homeowner can determine if a glass fuse in blown by performing a visual inspection and looking for a break in the thin wire and a brown discoloration in the center of the fuse. A ceramic fuse, however, shows no damage upon visual inspection. Testing a ceramic fuse is the only way to tell if the fuse has blown.

Things You'll Need

  • Ohmmeter or multimeter
  • Turn off the power supply to the appliance or other electrical device if the device is hard-wired. If the appliance has a plug, unplug the power cord.

  • Set an ohmmeter or multimeter dial to zero. Multimeters read both volts and ohms. If you are using a multimeter, set the multimeter to the ohm setting.

  • Touch one end of the fuse terminal with the black test probe and the other end of the fuse terminal with the red test probe.

  • Read the ohmmeter display. If the display shows the needle at zero or the digital display shows zero, the fuse is in good working condition. Any other reading above zero indicates the fuse is no longer working and has blown.

Tips & Warnings

  • If the ceramic fuse has blown, inspect the appliance's electrical circuitry to determine the cause of the blown fuse. Some fuses blow due to a power surge or age, while others blow because of electrical problems with the appliance or electrical device.
  • Do not attempt to test ceramic fuses when the power supply is connected; the current can cause physical harm to the tester and the meter.

Related Searches


  • "Home Repair and Improvement"; Creative Homeowner Editors; 2006
  • "Basic Wiring"; Time-Life Editors; 1989
  • Photo Credit Jupiterimages/Polka Dot/Getty Images
Promoted By Zergnet


You May Also Like

  • Electrical Fuse Identification

    While it's not that complicated to correctly identify electrical fuses, it is an activity that requires attention to detail when going about...

  • Difference Between Ceramic & Glass Fuses

    A fuse protects electrical appliances and equipment by breaking the electrical circuit in the event of an overload of current or a...

  • How to Replace a Blown Fuse

    The next time someone turns on the hair dryer, microwave and toaster oven all at once and sends your house's circuits into...

  • How to Test a Fuse

    Some older homes still exist where the electric is protected by fuses rather than more modern circuit breakers. With this type of...

  • How to Know When Fuses Are Blown

    The electricity in your home is carried by electrical circuits. If these circuits overload or surge, the electrical output could damage the...

  • How to Use a Volt Ohmmeter to Test a 20-Amp Fuse

    You can test a fuse using either a digital volt-ohmmeter or an analog volt-ohmmeter. The digital multimeter uses a LCD to indicate...

  • How to Find a Blown Fuse

    A blown fuse can occur when a device in the home, such as a hair dryer, overloads the electrical grid. The fuse...

  • How to Check Fuses in the Home

    When power goes out to only one part of the home, the fault may be a blown fuse. Fuse elements are made...

  • How to Tell If a Thermal Fuse Is Blown

    Thermal fuses are fire-prevention safety components that can be found in most modern appliances. The function of a thermal fuse is to...

Related Searches

Check It Out

22 DIY Ways to Update Your Home on a Small Budget

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!