Product Offering

Micro Fuse

Micro Fuse
Data Sheets »

A Micro style fuse is a radial leaded subminiature fuse offered in either a cylindrical or rectangular form factor. Micro fuses were originally designed for the U.S. Space Program. Micro fuses are made with either glass, plastic or metal bodies. They are designed to be electrically equivalent to minature glass cartridge fuses in a smaller package with higher tolerance to impact and vibration. Micro fuses can plug in to a PC board mounted fuse holder. Voltage ratings typically range from 65 volts AC to 300 volts AC. Micro fuses with voltage ratings up to 450 volts DC are also available. Micro fuses are offered in both fast acting or time lag versions. They are typically built in accordance with UL 248-14 and CSA C22.2/No.248.14 or IEC 60127-3 standards. Some series are also offered in MIL Spec versions.The IEC 60127-3 series are offered in several versions:

IEC DesignationOpening SpeedBreaking CapacityVoltage RatingLeads
IEC 127-3, Sheet IQuick ActingLow125VRadial
IEC 127-3, Sheet IIQuick ActingLow125VAxial
IEC 127-3, Sheet IIIQuick ActingLow250VRadial/Axial
IEC 127-3, Sheet IVTime LagLow250VRadial/Axial



Littelfuse, Bussmann and Schurter offer micro fuses. Littelfuse brand names include TR5®, TR3 ®, TE5 ® and TE3 ®. Bussmann brand names include PC-Tron ®.