Basic meter use: When testing a fuse with a Volt-Ohm meter (digital multimeter), which measurement setting should you use?

Difficulty: Easy

Correct Answer: OHMS

Explanation:


Introduction / Context:
A fuse is a passive component intended to be either continuous (very low resistance) or open (infinite resistance). Selecting the proper multimeter function ensures a quick and safe continuity check without powering the circuit under test.


Given Data / Assumptions:

  • The fuse is removed from the circuit or the circuit is fully powered off.
  • A standard digital multimeter with AC, DC, current, and resistance ranges is available.


Concept / Approach:
Continuity is determined using the resistance (ohms) function. A good fuse measures near 0 ohms (or beeps in continuity mode). Using AC or DC voltage ranges does not reveal continuity in an unpowered fuse. Current (amps) mode is dangerous if placed across a component because it effectively shorts the meter leads through the meter shunt.


Step-by-Step Solution:

Power the device off and, if possible, remove the fuse from its holder.Set the meter to OHMS or continuity.Touch probes to both ends of the fuse; observe a near-zero reading for a good fuse.If the reading is OL or very high, the fuse is blown.


Verification / Alternative check:
Use continuity tone if available; a steady tone indicates a good fuse. Visual inspection for a broken element can support the measurement but is not definitive.


Why Other Options Are Wrong:
AC and DC ranges read voltages, not continuity. AMPS range risks meter damage and blown meter fuse.


Common Pitfalls:
Testing in-circuit can produce misleading parallel paths; remove power and isolate the fuse when possible.


Final Answer:
OHMS

More Questions from Computer Hardware

Discussion & Comments

No comments yet. Be the first to comment!
Join Discussion