While the size of the 5 × 20 fuse is larger in comparison to a typical miniature 250 Volt SMD fuse, it provides electrical characteristics beyond what SMD fuse technology can provide today. The FST/SPT series includes the same slow reaction time as the standard time-lag 5 × 20 mm fuses according to IEC 127-2. The FTT offers a super time-lag opening. Time-lag fuses withstand current surge or repeated pulse currents. The FST has a current range of up to 20 Amps at 250 volts AC. The SPT type offers a high-breaking capacity of up to 1500 Amps at 250 Volts AC, allowing for safe interruption of dangerous fault.
Reflow and wave solderability for the SMD 5 × 20 mm fuses is 235°C for 2 seconds; soldering heat resistance is 260°C/10 seconds.