'Radio' fuses

ghostlymoron

ghostlymoron

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My little switch panel takes small glass fuses sold as radio fuses at Halfords. I accidentally shorted one of my internal lights while reconnecting it with my clumsy fingers and blew the fuse. I need a replacement for the blown one plus a few spares. Where else are these available?
 
ghostlymoron said:
My little switch panel takes small glass fuses sold as radio fuses at Halfords. I accidentally shorted one of my internal lights while reconnecting it with my clumsy fingers and blew the fuse. I need a replacement for the blown one plus a few spares. Where else are these available?
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It would be helpful if you gave the physical size of the fuse and the rating you are looking for.
 
I should think Ebay has a zillion listings for fuses. If you need one in a hurry just about any chandler will sell you one. Maplins, Wilco, almost any motor factor etc etc.

EDIT : Ebay search : glass fuse 8,778 listings
 
Maplins, RS, Farnell, Element 14........ ebay..
measure its length (probably 20mm) and search for that + glass fuse.

More technical, read the legend on the end cap it will have Amp rating and a code letter for speed of blow eg 1,25A T
 
For convenience I would go to Halfords. There's an out of town branch with free parking under 3 miles away

If I was ordering and wanted/ was prepared to buy in packs of 10 I would almost certainly buy from Maplin. But the nearest branch is over 7 miles away

Sod wading through a zillion ebay listings even if it might save 0.1 p per fuse if I could get them from Maplin
 
VicS said:
Sod wading through a zillion ebay listings even if it might save 0.1 p per fuse if I could get them from Maplin
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Sod travelling to Maplin (even though it's less than a mile away) if I can type "20mm glass fuse" into eBay, sort by price+postage, and click "Buy Now" on the first link :)

They're all the same anyway, so no wading required.

Pete
 
Those little 'Holt' packets of small screws, bulbs etc that seem present in almost every chandlery are a useful source of such parts. Possibly a little over priced but no postage charges and possibly no fuel used in travelling if such a place exists near your boat mooring.
I recently bought a navigation lamp bulb that was in fact competitively priced compared against the internet.
 
prv said:
Sod travelling to Maplin (even though it's less than a mile away) if I can type "20mm glass fuse" into eBay, sort by price+postage, and click "Buy Now" on the first link :)

They're all the same anyway, so no wading required.

Pete
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+1 next day delivery too. Or better still get rid of the horrible things, a breaker will fit the same hole.
 
ghostlymoron said:
http://cpc.farnell.com/bussmann-by-eaton/s500-10-r/fuse-quick-blow-10a-glass-5x20mm/dp/FF02905
I've found this which seems to fit the spec. I presume the voltage rating doesn't matter, 10a is 10a. Some seem to quote another 'ampage' as well, what's the significance of this?
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Voltage rating can be important in some cases, but not this one, when they blow they make an air gap, if the voltage in the circuit can jump that gap then the fuse wont be working properly.

The main current value is the one you are most interested in, thats what it will blow at (in the time given by the spec) the other rating, the one you linked is 100A is the maximum it can safely handle without blowing lil bits of glass all over your panel. Buy, you say, if it blows at 10A, how could you ever get 100A through it. The answers is very briefly in extreme situations, like, if you use alternator sized cable to and from the panel and somehow this poor lil fuse managed to directly short out those wires.
 
Thanks for that explanation, Dougal. My lil boat doesn't have an alternator so no huge power source or large cables.
Dougal Tolan said:
Voltage rating can be important in some cases, but not this one, when they blow they make an air gap, if the voltage in the circuit can jump that gap then the fuse wont be working properly.

The main current value is the one you are most interested in, thats what it will blow at (in the time given by the spec) the other rating, the one you linked is 100A is the maximum it can safely handle without blowing lil bits of glass all over your panel. Buy, you say, if it blows at 10A, how could you ever get 100A through it. The answers is very briefly in extreme situations, like, if you use alternator sized cable to and from the panel and somehow this poor lil fuse managed to directly short out those wires.
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ghostlymoron said:
Thanks for that explanation, Dougal. My lil boat doesn't have an alternator so no huge power source or large cables.
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The potential current that could be delivered will be that of your power supply/battery, possibly far greater than an alternator is capable of producing if it is a 12v lead acid one or similar.
 
ghostlymoron said:
My little switch panel takes small glass fuses sold as radio fuses at Halfords. I accidentally shorted one of my internal lights while reconnecting it with my clumsy fingers and blew the fuse. I need a replacement for the blown one plus a few spares. Where else are these available?
Click to expand...

Send me the details and I'll happily share some of the amazing stock we have amassed over the years.
 
ghostlymoron said:
My little switch panel takes small glass fuses sold as radio fuses at Halfords. I accidentally shorted one of my internal lights while reconnecting it with my clumsy fingers and blew the fuse. I need a replacement for the blown one plus a few spares. Where else are these available?
Click to expand...

The 20mm long fuse is a GMA type-as in GMA 5 5amp
The older 1 1/4" x 1/4" fuse is an AGC type- as in AGC 5 5amp
These are the two most common fuses found in DC boat ckts.
I won't bother with "arc over" voltage ratings for DC use,because a fuse rated 32VDC will blow properly & not arc over on 12,24,32VDC
These same fuses are commonly available in 250V rating,for no arc over on voltages up to 250V,so they will work properly on 12,24,32VDC.
Fast Blow is the most commonly available version of the GMA & AGC style fuse & is the proper type to use for any fixed load,such as electronics,lights ,etc.
You might consider a Slow Blow version for a motor load,such as a winch,if you are blowing fuses due to < 1 second surge on start up.,or short term heavy winch (over)load,though,IMHO,a breaker is much more sensible/economical in these cases.
You can usually recognize a Slow Blow by the use of a coiled wire,ceramic,etc. as it's internal element-but not always.

The above is not 100% fact for all fuses on a DC boat,but it is a good guide.

http://www.littelfuse.com/~/media/automotive/fuse_selection_chart.pdf


Edit: Look what I found by Google- Not sure if this still applies to UK
http://www.groups.tr-register.co.uk...ectrical Fuse - English Lucas Vs USA BUSS.pdf
 
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