1A fuse in a 13A plug - what will happen?

Post new thread
Search the forum,

Discuss 1A fuse in a 13A plug - what will happen? in the Australia area at ElectriciansForums.net

D

Discharged

I'm trying to explain to my kid (8) why were have fuses in plugs, and he found a 1A glass fuse lying 'round and he asked me if we could put that into a 13A plug. I said 'no' it would blow if you plugged into the mains.

Then I wondered if that really would happen... So thought I'd better ask here for clarification.

What does happen if you put a too-lower rated a fuse into a plug? To my mind, what happens depends on the appliance being supplied - what current it draws.

Any idea on this, please?
 
Well first of all it would depend on the load so if you put it in a kettle,iron,toaster,washing machine the fuse would blow but if you put it in a standard lamp it would work but when the lamp or bulb comes to the end of its life then it could blow the fuse
 
Thanks for that. So these 1A glass fuses would typically be aimed at protecting the simple, low demands of a much smaller appliance, like a clock radio perhaps?
 
Yes but there is a catch you cannot use these glass fuses in a plug top you have to use the same type of fuse and these are rated as 1,2,3,5,10,13 amps but most common fuses used are 3 and 13 amps in a domestic property the 1,2,5,10 are more common in a worplace

So Kettle ,toaster,washing machine, would be 13 amps
Standard light, PC, printer,clock radio would be 3 amps
 
Last edited by a moderator:
simply put, a 1A fuse will withstand a wattage if 230watts indefinitely, but can take around 1.45x that for up to an hour before popping.
 
but you get glass fuses in alarm panels and other things to . so i dont think it will explode unless you shoe a high voltage through, and even then i'm not sure
 
1amp fuses are used in 2 pin shaver adaptors but even then they are ceramic and not glass, glass fuses are used mainly to protect low current circuits on pcbs as far as i've found. Glass fuse in a plug with a faulty circuit might shatter the glass whereas the ceramic fuses contain the arc. If you powered say a vacuum cleaner or toaster with a 1 amp fused plug I doubt it'd even go bang it'd just melt the fuse element straight away. Interesting test all the same !!!!!
 
Hi,
It all depends on the prospective fault current and energy avaliable into a fault. A glass fuse can clear a fault of 35A and in practice a bit more, ok for the safety low voltage side of some power supplies. The test shown is a fuse subject to a current of about 6,000 amps and has a lot more energy avaliable!!
 
all interesting theories.......slightly undone by the fact that a glass 20mm fuse and a cartridge fuse are different sizes.
kitkat wrappers would be required.
 
kippaxkid said:
all interesting theories.......slightly undone by the fact that a glass 20mm fuse and a cartridge fuse are different sizes.
kitkat wrappers would be required.
Click to expand...
Wrong! I have 1 inch, 1A, LV, glass cartridge and 1 inch, 1A, BS1362, HBC, Ceramic cartridge fuses in front of me as I type.
 
Discharged said:
I'm trying to explain to my kid (8) why were have fuses in plugs, and he found a 1A glass fuse lying 'round and he asked me if we could put that into a 13A plug. I said 'no' it would blow if you plugged into the mains.

Then I wondered if that really would happen... So thought I'd better ask here for clarification.

What does happen if you put a too-lower rated a fuse into a plug? To my mind, what happens depends on the appliance being supplied - what current it draws.

Any idea on this, please?
Click to expand...

A glass fuse does not comply with BS1362 for a start so should not be fitted to a plug top.
 
Last edited:
Glass fuses should not be used as they do not comply with any B.S. , being glass they can shatter leaving glass , creating a danger , hence why they are ceramic to retain the molten metal and can be removed without danger of injury

What would happens depends on the rating of the glass fuse 12v 3amp , would pop if you put it in a toaster plug, 240v 13amp glass fuse would work , but not advised

JAmie
 
Sorry about that. My mistake. Didn't realise that 20mm was an inch........ (better half will be quite pleased with the reassessment.)
Back to the fuses.

(Why do I get sucked in??????)

A HBC fuse is not a plug top fuse.
Go round the house and see if you can find a three pin plug that doesn't have scrunched up baco foil in it, take out the fuse and measure it. You may notice a difference.
Ever wondered why there are so many styles of fuses?
 
BS1362 fuse must be fitted to a Plug. 3a up to 700w, and 13a above 700w, unless the appliance manufacturer instructions state otherwise.

Cheers...........Howard
 
kippaxkid said:
Sorry about that. My mistake. Didn't realise that 20mm was an inch........ (better half will be quite pleased with the reassessment.)
Back to the fuses.

(Why do I get sucked in??????)

A HBC fuse is not a plug top fuse.
Go round the house and see if you can find a three pin plug that doesn't have scrunched up baco foil in it, take out the fuse and measure it. You may notice a difference.
Ever wondered why there are so many styles of fuses?
Click to expand...

You can not be serious ? 25mm is an inch 20mm is roughly 3/4 inch think you need to back to school:33:
 
Last edited:
Cyberprog said:
I do wonder about that over 700w should be 13A, had a Belt Sander from B&Q with .75mm2 cable, and a 13A fuse...
Click to expand...
The reason I got for a similar situation was that "it will likely fail within the plug or the appliance and therefore failsafe" I still don't like it at all, especially when some 2377 tutors are telling students to swap any plug fuses for 3 or 13 amp fuses using the <700W = 3A and >700W = 13A unless its IT kit and to do the swap to "look like your doing something"....personally it feels like watering down of safety and a serious dumbing down of standards, I could understand if say all new appliances were supplied with either 0.75mm2 and a 3A fuse or 1.5mm2 and a 13A fuse, but a lot of own brand stuff is coming with H03.... 0.75mm2 flex and 13A fuses sometimes with a load exceeding 2Kw....I won't be surprised to read of someone killed in a house fire due to overheated flex starting a fire, or a shock due to degraded insulation.......
 
I guess this is going off-topic, but what is the reason you have such a tiny wire in the fuse (any fuse), yet all that current can pass through all the larger wires in the cabling without blowing the fuse the moment ANY power is switched on.

Perhaps this is a rhetorical question - we all know what fuses are for, but I was interested in the mechanics of it... but then...

Why have cabling such as 1.5mm or 2.5mm when the fuse size does not alter? What does the larger cable permit that the smaller does not?
 
"Why have cabling such as 1.5mm or 2.5mm when the fuse size does not alter? What does the larger cable permit that the smaller does not?"

The larger cables have a lower voltage drop than smaller cables so if you had a long piece of fuse wire (small) it would have a relativly high resistance compared to say a 1.5mm wire and get warm/hot thereby dissapating some of the energy you want to get to your appliance. Fuse wire gets warm in the fuse if it is run near its capacity but the length involved is so small the voltage drop is negligable.
 
Why would they teach about inches/feet in school? Its been replaced for years!

My Mrs had better stop pestering me for my 6 inch todger and start getting metricated then
icon6.png
icon7.png
 
Des 56 said:
Why would they teach about inches/feet in school? Its been replaced for years!

My Mrs had better stop pestering me for my 6 inch todger and start getting metricated then
icon6.png
icon7.png
Click to expand...

When the Government ordered us to all go metric back in '73 (I think) I was working in engineering.

All out Company did was redraw all the engineering drawings onto metric sized drawing paper & change the Imperial dimensions to Metric.

All our measuring instruments (micrometers etc) were all Imperial, as were the graduated dials on all the machines, so whenever a drawing for a component arrived on the shop floor, the machinist would spend half an hour or so with his calculator & pencil changing all the Metric dimensions back to Imperial.

The only other concession our boss made with regard to "Going Metric" was to buy one 25mm - 50mm external micrometer which he then insisted on calling the "1" - 2" Metric micrometer" !!!

I worked in a further 5 engineering companies up until 1982 and none of them had fully embraced the Metric System.

(and why should we?? ........... the Americans didn't!!)
 
Ian wrote:"You can not be serious ? 25mm is an inch 20mm is roughly 3/4 inch think you need to back to school"

you need to read the posting I was replying to, and the sarcasm in my response will come shining through like a beacon...............

(Reads better knowing what the comment was about, dunnit?)
 
I am also old enough to remember when things on a roll had to be sold in metric lengths, but perversely widths were still imperial. ( so very last century!!)

typical conversation>
100 yards of visqueen please.
it's a 100 metres these days mate. Get with the times....Now do you want it 9 foot wide or 12 foot?

We used to rule the world, you know
 
I'm approaching bus pass age. Every morning I have to sit on the end of the bed until the deafening noise of my bones finishes before i stand up,and all that takes longer than the drive to work, and you STILL call me junior
 
When I went to school they kept on changing the units of measure for things due to metrication. So I learnt foot pounds inches, Centimeter gramm seconds, metre kilogram seconds with poundals, newtons, and all sorts of other things that I ca
 
can no longer remember. As a result I have absolutly no idea what goes with what. While I can use these new fangled things I still understand inches and feet best.

I managed to press something which posted the last reply part way through. so this is the rest.
 
Plugging in a 1amp fuse on a 13amp appliance wouldnt make it go bang it would just heat the fuse up rapidly and it will break, an appliance with a motor may make it pop a little with the inrush but it would need a fault condition to make it vapouries the copper wire leaving the familiar copper coated glass effect, at standard voltage of 230v its possible for the vapourised glass coating to still give a path, some ceramics avoid this issue by filling the fuse with sand so if it was to vapourise the wire it is extremely unlikely to leave a copper track that the cuurent could still use.
Lower voltage are less likely to be able to track across a blown fuse and glass is ideal as you can see if the fusewire is intact and if not whether a short blew it or a overload.
 
darkwood said:
Plugging in a 1amp fuse on a 13amp appliance wouldnt make it go bang it would just heat the fuse up rapidly and it will break, an appliance with a motor may make it pop a little with the inrush but it would need a fault condition to make it vapouries the copper wire leaving the familiar copper coated glass effect, at standard voltage of 230v its possible for the vapourised glass coating to still give a path, some ceramics avoid this issue by filling the fuse with sand so if it was to vapourise the wire it is extremely unlikely to leave a copper track that the cuurent could still use.
Lower voltage are less likely to be able to track across a blown fuse and glass is ideal as you can see if the fusewire is intact and if not whether a short blew it or a overload.
Click to expand...

The BS Standard (BS1362) requires them to be filled IIRC with sand.
 
Cyberprog said:
The BS Standard (BS1362) requires them to be filled IIRC with sand.
Click to expand...
When i said 'some ceramics' was refering to the many varieties of ceramic fuses but yes agree BS1362 requires the sand for the reason ive given but other ceramic fuses do employ different methods but they also have a physical size advantage, BS1362 are very small given rise to potential tracking hence the requirement.
 
i thought it was 25.4. and anyway metric system is stupid. ever heard anyone say " not many of those in a killergram"?
 
Last edited:
Well spotted Lee
Lenny maybe try specsavers lol

Thread closed.
 
As alot of the posters in this thread no longer frequent the forum and given the age of the thread, I'll close it, if anyone want to discuss this thread further then they can open a new one for a fresh discussion.

Damn that GMES ...got me back for mocking him earlier lol ... you closed it same time as me but beat me to it tut tut!!!:furious3:
 
Last edited:

Reply to 1A fuse in a 13A plug - what will happen? in the Australia area at ElectriciansForums.net

Similar Threads

B
Plugs and Fuses - Help understanding symbols (PC/Monitor)
I have a question which is confusing me and I cannot find a definitive answer and I hope someone can help. So I have a PC and Monitor and I have...
Replies
4
Views
496
littlespark
littlespark
TheArcMan
UK Selectivity, mcb vs fuse...
Hi all, Been browsing these forums for a while, always great to learn a new way to skin the same cat. Anyway, cut a long story short, was an...
Replies
11
Views
783
davesparks
davesparks
S
Electric iron intermittently goes bang
Hi all, Was speaking to a family member recently, he told me his iron recently made a bang and flash as he plugged it in to the socket, and could...
Replies
14
Views
2K
loz2754
loz2754
captaincaveman
How to get a 41A oven working on a 13A plug...?
I Knew it was going to be one of those days when my first customer couldn't understand why his 9.5kw standalone oven/hob kept cutting out because...
Replies
9
Views
2K
littlespark
littlespark
J
  • Locked
Replacing a 13A plug fuse with solid brass
I read once, never seen one for sale, that there is a solid brass replacement for the standard 13A fuse in a 13A plug. This is to eliminate the...
    • Dislike
2 3 4
Replies
162
Views
12K
westward10
westward10

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

YOUR Unread Posts

Tags

advice aus cable circuit course earth electric electrical electrician hello led light lighting lights looking new please question rcd socket supply switch testing training wiring
This website was designed, optimised and is hosted by untold.media Operating under the name Untold Media since 2001.
Tiling Advice
Back
Top