Ceramic Fuse Markings

Where many people go wrong is confusing the continuous fusing rating where the fuse pops with the smaller rating of continuous amps which is where fuse operates normally.

Ceramic fuse markings.

The more thermally stable fuse is typically filled with sand in order to prevent the conductive film from forming. 5x20mm iec fuse marking. The film is formed when a short circuit melts the fuse element causing a deposit to be seen on the inside of the fuse barrel as a film. These are ceramic barrel fuses similar to the bosch style.

I ve had a few enquiries about coloured bands on fuses and what value is denoted by the colours etc. When the fuse elements open there is more material for the vaporizing fuse metals to absorb into resulting in a very efficient and effective quenching of the fuse arc. What is the fuse marking according to iec standard 127 and how does this translates to littelfuse s 5x20mm fuse offerings. Glass fuse markings can provide a lot of information about the type of fuse so you know what to replace it with.

Fortunately few porcelain insulator styles u numbers have both dry process specimens with an embossed marking and wet process specimens with one of the other marking types. When replacing a lucas fuse with a non lucas glass type fuse you use the smallest rating for the new. If you want to know why you need a fuse or why to replace with the correct one see the fuses what and why page. It s essential that you replace a blown fuse with another of the same type.

Fuses come in many types and sizes including glass fuses which may be slow blow fuses or fast acting fuses. A ceramic fuse is built to withstand high temperatures. For more information on other markings found on fuses see the fuses. Element surface area to the glass ceramic absorption material.

Please see the attached file. Figure sf1 compares the multi layer design of our sff fuses with standard glass coated designs. Also what the meaning of various letter number combinations on circuit boards or labels.