Glass Cartridge Fuse Replacement

Question

Problem: Glass Cartridge Fuse Replacement. Solve this hands-on electronics task on EWskills.

Accepted Answer

1. Component Purpose

A multimeter’s current measurement path passes the measured current directly through the meter. If the user accidentally connects the meter across a voltage source while in current mode, a very large current flows through the meter.

The current measurement fuse protects the meter’s internal shunt resistor and circuitry from this fault current. A fast-blow fuse disconnects the path as quickly as possible to prevent internal damage.

Required: Glass Cartridge · 500mA (0.5A) · ≥250VAC · Fast Blow · 5mm × 20mm · Littelfuse · RoHS

2. How to Find It on DigiKey

Go to DigiKey.com → Circuit Protection → Fuses

Apply these filters:

Fuse Type → Cartridge, Glass
Current Rating (Amps) → 0.5A (500mA)
Voltage Rating - AC → 250V or higher
Response Time → Fast Blow
Package / Case → 5mm x 20mm
Manufacturer → Littelfuse Inc.
Part Status → Active

Important: This is a direct replacement fuse. Current rating, response time, and physical size must match exactly. Do not substitute with a different current or a slow-blow type.

3. Key Specifications & What They Mean

Specification	Required	Why
Fuse Type	Cartridge, Glass	Standard instrument-grade fuse body.
Current Rating	0.5A (500mA)	Must match instrument manual exactly.
Voltage Rating	≥250VAC	Meter may be used on mains circuits.
Response Time	Fast Blow	Quick disconnect to protect meter internals.
Size	5mm × 20mm	Must fit existing fuse holder in the meter.
Manufacturer	Littelfuse	Company AVL requirement.
RoHS	Yes	Compliance required.

4. Selecting a Safe, Production-Ready Part

The filtered list will show matching parts. Before you pick one, check: Is it Active? Is stock available? Is a datasheet available?

Full checklist: How to Select a Safe, Production-Ready Component — EWskills Guide

5. Filtered DigiKey Link

➡ View Matching Parts — Littelfuse, Glass Cartridge, 500mA, 250V, Fast Blow, 5x20mm

6. Glass Cartridge Fuse Replacement