Help recognising a fuse

[stallik]

This is clearly a 0.5amp fuse but I'm unsure of the symbol before the 37. Any ideas?
It's the display board on my old Zoom 9050 which has has stopped working. The fuse has blown. ( I hope ) because of some clag elsewhere on the board which was creating a short

[Rob Strand]

Most SMD parts have a making code which identifies the part but it is not the part number.
I can't identify the part from the code.

The package for that fuse isn't that common (I only see it in consumer products).  These days I see more SMD fuses in the resistor style packages like 1206, 0805.   From a replacement perspective you might be better off using one of these packages.  You will have to find one which fits the PCB footprint, at least in length.

You should be safe using a Slo-Blo fuse in that position.  Fast-Acting types are likely to fail unnecessarily down the track.

When you solder these SMD fuses, apply the minimum amount of heat as the heat from the soldering process can actually degrade the fuse.

[stallik]

Thanks Rob. I had a feeling that I wouldn't be able to get the same package. This is quite an old board now and the industry has moved on a pace in that time.

[Rob Strand]

I found a couple of examples.  They probably aren't the right fuse but I suspect they are the same package.
The thing to note is because the package is large the I^2 t rating of the fuse is higher.

Fast:  I^2 t   = 0.055
http://au.element14.com/littelfuse/0459-500ur/fuse-v-fast-acting-smd-500ma/dp/1596969RL

Slo-Blo:  I^2 t = 0.2
http://au.element14.com/littelfuse/0460-500ur/fuse-antisurge-smd-500ma/dp/1596977

Normal:  I^2 t = 0.032
http://www.daitotusin.co.jp/contents/c_j/Daito_J.pdf/CMF.pdf


This modern 1206 *slo-blo* fuse has an I^2 t of 0.03.
http://au.element14.com/bourns/sf-1206s050-2/fuse-500ma-63vdc-smd-slow-blow/dp/1652158


So it's probably best to go with a slo-blo.

[stallik]

Well Rob, I've just learned my lesson not to read replies when I'm half asleep and am completely re writing this.
The Daito fuse is the one, just got to source a couple. Thanks again