Buzz
Steps
Understanding Fuses and Multimeters
Grasp the concept of fuses. Fuses are essentially wires designed with a limited lifespan. Their purpose is to safeguard valuable electrical equipment and prevent fires, particularly in residential settings, caused by power surges. When subjected to excessive power, fuses will 'burn out,' physically breaking the circuit and halting the flow of current. Various types of fuses exist, but their distinctions are primarily superficial. Below are descriptions of the two most common types:
- The cartridge fuse, cylindrical in shape, has been prevalent in various devices for decades, ranging from household appliances to small electronics. It features metal contacts or terminals at both ends and primarily comprises a tube housing the wire.
- The blade fuse, widely used in automotive applications over the past few decades, resembles the plug of a power cord. It consists of two metal prongs protruding from a plastic casing containing the wire. Previously, many vehicles utilized small glass cartridge fuses. Blade fuses conveniently plug into panels, requiring minimal space to accommodate numerous fuses.
Discover the inner workings of a multimeter by exploring how it functions.
Comprehend the importance of testing fuses and its relevance in electrical systems.
Conducting Fuse Tests
Power down the equipment and extract the fuse securely.
Activate the meter and configure it to check continuity.
Place one lead on each end of the fuse and observe the display.
Since the fuse is essentially a single wire with no intricate components, it doesn't matter which lead is positive or negative.
Test the fuse.
Listen for a continuous beep from the multimeter as you press the probes against the fuse. If there's no sound, the fuse is blown and needs replacement.
- If you're using a digital multimeter set to measure resistance, start by touching the probes together to establish a baseline reading. Then place the probes on either side of the fuse and compare the readings. If they're similar, the fuse is intact. If you get no reading or see 'OL,' the fuse is blown.
- If the multimeter displays 'Open' or 'Not complete,' it indicates a broken fuse.
Tips:
- Modern household installations should ideally use circuit breakers and other fuse-less protective devices for enhanced safety. Consider upgrading old fuse installations to meet modern standards.
- For car fuses, most vehicles utilize colored 'blade' type fuses. Checking the top of the fuse in the fuse box will reveal whether the metal strip running along the visible top is intact (indicating a good fuse) or broken (indicating a blown fuse).
Warnings:
- Never substitute a blown or suspicious fuse with one with a higher rating. The rating ensures safe passage of current through the wiring. Always replace a fuse with the same rating as the old one, or lower.
- Avoid testing a fuse on equipment that is still powered on.
