On 24/11/16 04:36, wrote:
Frank Erskine wrote:
I don't know whether or not "intermediate" BS1362 fuses such as 5A or
7A are still available.

I've just given a packet of 5A fuses to my neighbour, they definitely
exist. In my toolbox I have packets of 3A, 5A and 13A.

jgh

I think you can even get 1.5A in that size. Used to see 10A but not for
years now.


--
€œSome people like to travel by train because it combines the slowness of
a car with the cramped public exposure of €¨an airplane.€�

Dennis Miller

On 23/11/2016 1:23 PM, Roger Hayter wrote:
Dave Plowman (News) wrote:

In article ,
wrote:
So those chinese goods with barely 0.1mm2 are uprotected on a 13A fuse.

I ask again. Why are you buying such things that you know to be rubbish?
If you're not, no point in telling the world they should fit an
appropriate fuse, as they're not listening. And wouldn't understand
anyway.

And that 1960s hifi with 0.1mm dia mains wiring inside ditto.

Must have been real rubbish if it didn't have an equipment fuse.

Interestingly, I just had a counter-example where a 3A fuse might have
prevented equipment damage due to a fault. A Grundfos pump (mention
the name because it is the second one to do the same) failed
short-circuit and melted a trace on the controller PCB, without actually
blowing the 13A plug fuse or tripping the MCB. A 3A fuse might have
prevented this. However, I haven't checked whether the oil pump inrush
current is too high for a 3A fuse yet.



For me, this is where the fuse rating lies. Estimate the working current
of the device and limit the current input. Any mishaps handling the
circuitry will have the same current limit. Could be a life saver?

....Ray.

....Ray.

On Wednesday, 23 November 2016 14:47:01 UTC, Dave Plowman (News) wrote:
In article ,
whisky-dave wrote:
On Wednesday, 23 November 2016 11:07:00 UTC, Dave Plowman (News) wrote:
In article ,
wrote:
So those chinese goods with barely 0.1mm2 are uprotected on a 13A
fuse.

I ask again. Why are you buying such things that you know to be
rubbish?

Lots of people buy cheap **** in the hope it will do a simialar thing to
a full priced version of the same thing. Some just because it looks the
same and others might think they own a better product than they actually
do, or it's an image thing where they fool themselves too. if people
didn't want such things we wouldn't be getting fake things coming into
the UK or anywhere else.

There's a very big difference between a fake and something merely sold as
cheaply as possible. The former is an attempt to deceive. So everything
else goes out the window. The latter to capture a sector of the market.

and the middle ground were you get 'fake' chennel no.5 a friend of mine used to be a lookout down oxford street while somneone sold such things out of a suitcase.


A low cost product may or may not be value for money.

But they are rarely if ever faked.

The obvious one
being power tools. A Lidl cordless drill at 40 quid almost certainly isn't
as good as a 100 quid Makita. But may perform DIY tasks more than
adequately.

But what if it's branded Makita and cost £40.


If you're not, no point in telling the world they should fit an
appropriate fuse, as they're not listening. And wouldn't understand
anyway.

It can also cost more to adhere to any regualtions that are imposed by
an authority.

Anything on sale in the UK should conform to UK regs. No point in having
them if not enforced.

I guess you've never watched Rip of Britain.





I've got a nice big selection box of 20mm fuses. Hope they don't have a
shelf life. ;-)

me too 100s of them also 5/8th and 1 1/4 inches from 50ma to 15 amps.
The shelf I keep them on is metal so I think it will last a while I might be worried if it was wooden, but then the lastest from steven harkwins is that he thinks the human race (as we know it) only has 1000 years left.

On Thursday, 24 November 2016 11:22:45 UTC, whisky-dave wrote:
On Wednesday, 23 November 2016 14:47:01 UTC, Dave Plowman (News) wrote:
In article ,
whisky-dave wrote:
On Wednesday, 23 November 2016 11:07:00 UTC, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Having read the last round of replies I can see no point in continuing. Commenting further would only invite more nonfact and nonlogic. I agree to differ.


NT

On 24/11/2016 10:36, RayL12 wrote:
On 23/11/2016 1:23 PM, Roger Hayter wrote:
Dave Plowman (News) wrote:

In article ,
wrote:
So those chinese goods with barely 0.1mm2 are uprotected on a 13A fuse.

I ask again. Why are you buying such things that you know to be rubbish?
If you're not, no point in telling the world they should fit an
appropriate fuse, as they're not listening. And wouldn't understand
anyway.

And that 1960s hifi with 0.1mm dia mains wiring inside ditto.

Must have been real rubbish if it didn't have an equipment fuse.

Interestingly, I just had a counter-example where a 3A fuse might have
prevented equipment damage due to a fault. A Grundfos pump (mention
the name because it is the second one to do the same) failed
short-circuit and melted a trace on the controller PCB, without actually
blowing the 13A plug fuse or tripping the MCB. A 3A fuse might have
prevented this. However, I haven't checked whether the oil pump inrush
current is too high for a 3A fuse yet.



For me, this is where the fuse rating lies. Estimate the working current
of the device and limit the current input. Any mishaps handling the
circuitry will have the same current limit. Could be a life saver?


BS1362 fuses are quite sloppy in tolerance:

wiki.diyfaq.org.uk/index.php/File:BS1362FusingTime.png

So the 1 sec fusing time for a 3A fuse could represent anything from say
5A to 12A



--
Cheers,

John.

/================================================== ===============\
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|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Thursday, 24 November 2016 23:28:26 UTC, John Rumm wrote:
On 24/11/2016 10:36, RayL12 wrote:
On 23/11/2016 1:23 PM, Roger Hayter wrote:
Dave Plowman (News) wrote:

In article ,
wrote:
So those chinese goods with barely 0.1mm2 are uprotected on a 13A fuse.

I ask again. Why are you buying such things that you know to be rubbish?
If you're not, no point in telling the world they should fit an
appropriate fuse, as they're not listening. And wouldn't understand
anyway.

And that 1960s hifi with 0.1mm dia mains wiring inside ditto.

Must have been real rubbish if it didn't have an equipment fuse.

Interestingly, I just had a counter-example where a 3A fuse might have
prevented equipment damage due to a fault. A Grundfos pump (mention
the name because it is the second one to do the same) failed
short-circuit and melted a trace on the controller PCB, without actually
blowing the 13A plug fuse or tripping the MCB. A 3A fuse might have
prevented this. However, I haven't checked whether the oil pump inrush
current is too high for a 3A fuse yet.



For me, this is where the fuse rating lies. Estimate the working current
of the device and limit the current input. Any mishaps handling the
circuitry will have the same current limit. Could be a life saver?


BS1362 fuses are quite sloppy in tolerance:

wiki.diyfaq.org.uk/index.php/File:BS1362FusingTime.png

So the 1 sec fusing time for a 3A fuse could represent anything from say
5A to 12A

Which is also why yuo shouldn;t use say a 3 amp fuse in a device that takes 3 amps for any lenght of time, because the fuse will run how and wonlt blow but could cause a fire which is why you'd use a 13 amp fuse now.
We still have 1 , 2, 3, 5, 7, 10 & 13amp fuses but the current :-) way of doing this is to have a 3 amp fuse or a 13 amp fuse in the plug.

In article ,
whisky-dave wrote:
Which is also why yuo shouldn;t use say a 3 amp fuse in a device that
takes 3 amps for any lenght of time, because the fuse will run how and
wonlt blow but could cause a fire

I sincerely hope you never go near the design of anything.

--
*Great groups from little icons grow *

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 22 Nov 2016 00:58:07 -0000, John Rumm wrote:

On 21/11/2016 21:19, wrote:
On Monday, 21 November 2016 12:53:57 UTC, John Rumm wrote:
On 21/11/2016 04:09, tabbypurr wrote:
On Sunday, 20 November 2016 22:46:03 UTC, John Rumm wrote:
On 20/11/2016 21:55, tabbypurr wrote:

It's called a straw man when you invent something totally
brainless, claim the other person said it then criticise it.
And it ain't worth discussing.

So grow up and stop doing it then.

Oh. Silly me I thought it was you that invented & argued about
the idea of changing extension lead fuses every time something
different was plugged in.

You said "When you have an extension lead plugged into another, or
an old appliance, or something bought from China, it certainly
does."

ie it does matter what fuse you use.

So, if you are not alluding to selecting an appropriate fuse for
the extension lead, what are you suggesting?

Let's get it clear in case anyone is still confused. For all plugs I
pick the lowest fuse that will reliably serve. It's what I recommend
others to do too. If folk don't want to, it's not my life, it's
theirs.

And how do you know what that value is? Given in many cases its not as
simple as looking at the nominal run current - you may need to take into
account inrush.

It's quite simple, you divide the watts by the volts and put a fuse of that value (or the next one up if the result is inbetween). If the fuse blows when you turn it on, you need a bigger one for inrush.

--
FOR SALE BY OWNER. Complete set of Encyclopedia Britannica , 45 volumes.
Excellent condition, £200 or best offer.
No longer needed, got married, wife knows everything.

On Tue, 22 Nov 2016 20:23:19 -0000, John Rumm wrote:

On 22/11/2016 12:06, Roger Hayter wrote:
John Rumm wrote:

On 21/11/2016 21:19, wrote:


And for the sake of clarity, I shall now state what I thought was
obvious, but perhaps isn't to some. A 5A extension lead is usable for
loads up to 5A continuous, and is thus best protected by a 5A fuse.

Obvious enough - you need the fuse for fault and overload protection in
that case. One of the reasons why 5A leads are far less freely available
than in the past.

The fact the fuse can't provide overload protection in the common
circumstance of the lead being used without being unreeled is probably
why they often have heat operated overload cutouts in the reel.

For extension leads on a reel, yes.

There is a second class of lead which are the multiway sockets on a
(typically shorter) lead. There the 13A fuse also has to provide
overload protection since its possible for the user to abuse them. (and
this is also a cases where I would have some sympathy with fittings say
a 10A fuse to some of the cheaper examples of those since tests have
shown a number to not really be capable of sustained 13A load).

Dunno if it was the fuse allowing 13 amps through, or the extension not allowing 13A continuous, but I've seen someone melt 4 way strips by plugging in two tumble driers and two washing machines. They really should make a 13A fuse melt if it gets 14A for more than a minute.

--
Drive defensively. Buy a tank.

On Wed, 23 Nov 2016 00:01:53 -0000, John Rumm wrote:

On 22/11/2016 22:47, wrote:
On Tuesday, 22 November 2016 20:23:21 UTC, John Rumm wrote:
On 22/11/2016 12:06, Roger Hayter wrote:

Realistically the fuse is not going to provide overload protection, just
fault protection for the flex for modern small electronic appliances. I
thought that was what you said earlier in the thread?

Indeed it is. I was just trying to get the bottom of what Nige was
actually attempting to achieve with his lowest possible fuse that's
adequate scenario - I understand the adequate bit - it must offer fault
protection, but assuming we have got past the "it gives adequate fault
protection" stage, there seem to be diminishing returns.

Depending on the appliance, it could end up being an exercise in blowing
lots of small fuses working your way up to the optimal one.

Most appliances are not going to need specific overload protection and
many that do may include a 750mA (or whatever) 20mm glass cartridge
fuse for the purpose. Those alone though won't provide fault protection
(inadequate breaking capacity usually), so sny BS1362 fuse in the plug
will do in many of those cases.

But a small significant percentage of appliances have neither short nor overload protection on a 13A fuse. Why you don't get that I really don't get.

I "get" that crusty old crap, and 5A extension leads need specific fusing.

I also get that if one understands these things there is no harm in
selecting a lower rated fuse.

However we live in a world where appliance designers accept that many
users won't be able to make a judgement call on this, and hence
designing them to remain safe on a 13A fuse is the only prudent option.

So you want every appliance to have a 13A cable? That's a bit daft.

--
Why was the "pap smear" called that?
If it'd been called the "**** Scrape," no one would ever have it done.

On Wed, 23 Nov 2016 12:59:10 -0000, John Rumm wrote:

On 23/11/2016 08:30, wrote:
On Wednesday, 23 November 2016 00:01:55 UTC, John Rumm wrote:
On 22/11/2016 22:47, tabbypurr wrote:
On Tuesday, 22 November 2016 20:23:21 UTC, John Rumm wrote:
On 22/11/2016 12:06, Roger Hayter wrote:

Realistically the fuse is not going to provide overload
protection, just fault protection for the flex for modern
small electronic appliances. I thought that was what you
said earlier in the thread?

Indeed it is. I was just trying to get the bottom of what Nige
was actually attempting to achieve with his lowest possible
fuse that's adequate scenario - I understand the adequate bit
- it must offer fault protection, but assuming we have got past
the "it gives adequate fault protection" stage, there seem to
be diminishing returns.

Depending on the appliance, it could end up being an exercise
in blowing lots of small fuses working your way up to the
optimal one.

Most appliances are not going to need specific overload
protection and many that do may include a 750mA (or whatever)
20mm glass cartridge fuse for the purpose. Those alone though
won't provide fault protection (inadequate breaking capacity
usually), so sny BS1362 fuse in the plug will do in many of
those cases.

But a small significant percentage of appliances have neither
short nor overload protection on a 13A fuse. Why you don't get
that I really don't get.

I "get" that crusty old crap, and 5A extension leads need specific
fusing.

and new crap that is often CE mismarked.

I am not sure what your fascination with dangerous and substandard goods
is in particular.

Yes there is loads of crap that is electrically unsafe and being sold
illegally.

Don't lul yourself into a false sense of security that sticking a 3A
fuse in it its going to suddenly make it safe - it will likely still be
dangerous!

The lack of fusing or inadequate mains cable is usually the tip of the
iceberg. Look closely and you will often see metalwork coupled directly
to mains,

For example?

--
I don't care what they say, I don't think "phone sex" is any fun at all, unless you happen to be in the same booth with her.

On Friday, 25 November 2016 14:28:31 UTC, Dave Plowman (News) wrote:
In article ,
whisky-dave wrote:
Which is also why yuo shouldn;t use say a 3 amp fuse in a device that
takes 3 amps for any lenght of time, because the fuse will run how and
wonlt blow but could cause a fire

I sincerely hope you never go near the design of anything.

I feel the same way about you replacing triaacs all the time because you lighting system isn;lt up to what yuor doing.

You carry on replacing triacs till the end, I prefer to find out where the fault is and correct that.


--
*Great groups from little icons grow *

Dave Plowman London SW
To e-mail, change noise into sound.

On Friday, 25 November 2016 16:13:14 UTC, whisky-dave wrote:

You carry on replacing triacs till the end, I prefer to find out where the fault is and correct that.

The fault is with your brain.

On 24/11/2016 11:28 PM, John Rumm wrote:
On 24/11/2016 10:36, RayL12 wrote:
On 23/11/2016 1:23 PM, Roger Hayter wrote:
Dave Plowman (News) wrote:

In article ,
wrote:
So those chinese goods with barely 0.1mm2 are uprotected on a 13A
fuse.

I ask again. Why are you buying such things that you know to be
rubbish?
If you're not, no point in telling the world they should fit an
appropriate fuse, as they're not listening. And wouldn't understand
anyway.

And that 1960s hifi with 0.1mm dia mains wiring inside ditto.

Must have been real rubbish if it didn't have an equipment fuse.

Interestingly, I just had a counter-example where a 3A fuse might have
prevented equipment damage due to a fault. A Grundfos pump (mention
the name because it is the second one to do the same) failed
short-circuit and melted a trace on the controller PCB, without actually
blowing the 13A plug fuse or tripping the MCB. A 3A fuse might have
prevented this. However, I haven't checked whether the oil pump inrush
current is too high for a 3A fuse yet.



For me, this is where the fuse rating lies. Estimate the working current
of the device and limit the current input. Any mishaps handling the
circuitry will have the same current limit. Could be a life saver?


BS1362 fuses are quite sloppy in tolerance:

wiki.diyfaq.org.uk/index.php/File:BS1362FusingTime.png

So the 1 sec fusing time for a 3A fuse could represent anything from say
5A to 12A





Yes, I can see that John. Fair comment.

On Friday, 25 November 2016 18:05:10 UTC, wrote:
On Friday, 25 November 2016 16:13:14 UTC, whisky-dave wrote:

You carry on replacing triacs till the end, I prefer to find out where the fault is and correct that.

The fault is with your brain.

I see you understand nothing and know even less.

Sir what will happen if a European oven with 13A main fuse rating is used in India where Standard power plugs are rated 16A after changing European plug to the Indian plug

On 22/09/17 15:52, wrote:
Sir what will happen if a European oven with 13A main fuse rating is used in India where Standard power plugs are rated 16A after changing European plug to the Indian plug


Not much - it's close enough to be safe in my opinion. You should be fine

On 22/09/2017 15:52, wrote:

Sir what will happen if a European oven with 13A main fuse rating is
used in India where Standard power plugs are rated 16A after changing
European plug to the Indian plug

Any appliance that is sold for use in europe should be designed such
that its flex has adequate fault protection from a 16A circuit breaker -
since that is what would be expected in most euro countries. The UK is
unusual with the general use of 32A circuits for socket circuits - and
hence the need for additional fusing at the point the appliance connects
to the circuit.


--
Cheers,

John.

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On 22/09/17 15:52, wrote:
Sir what will happen if a European oven with 13A main fuse rating is
used in India where Standard power plugs are rated 16A after changing
European plug to the Indian plug

Nothing much.
As long as what it is plugged into has a 16A fuse in it.



--
If you tell a lie big enough and keep repeating it, people will
eventually come to believe it. The lie can be maintained only for such
time as the State can shield the people from the political, economic
and/or military consequences of the lie. It thus becomes vitally
important for the State to use all of its powers to repress dissent, for
the truth is the mortal enemy of the lie, and thus by extension, the
truth is the greatest enemy of the State.

Joseph Goebbels

On Mon, 21 Nov 2016 22:13:13 +0000, John Rumm
wrote:

On 21/11/2016 21:45, bert wrote:
In article , "Dave Plowman (News)"
writes
In article ,
wrote:
How do you chose the "correct" fuse for an extension lead (assuming
the lead is designed for a 13A load)?

I can't imagine why you assume extension leads are all 13A rated. I
assure you they're not. 10A leads get a 10A fuse, 5A leads get a 5A fuse
etc. Hardly a challenge.

Rather silly given the average person won't have a clue how much current
things take. And if, say, a 5 amp fuse blew would likely fit a 13 amp
one.

Safer to make them all 13 amp. Much as has happened with all leads these
days.

How can a 13 amp fuse make it"SAFER" than a 5 amp one?

Not the fuse, the flex / appliance.

If you design your product so that it is adequately protected by a 13A
fuse, then there is nothing the user can do to make it unsafe.

If you design it so that its requires lower fusing, then it means there
is a danger of it having inadequate fault protection if the user fits a
13A fuse without appreciating the implications.

I have wondered about this. If an appliance is designed to EU
specifications (with a different plug for UK models) does this mean it
is designed to operate safely with a 16 amp fuse given that Euro and
Schuko etc plugs are unfused and I understand circuits are fused at 16
amps.

On 22/09/2017 19:55, Scott wrote:
On Mon, 21 Nov 2016 22:13:13 +0000, John Rumm
wrote:

On 21/11/2016 21:45, bert wrote:
In article , "Dave Plowman (News)"
writes
In article ,
wrote:
How do you chose the "correct" fuse for an extension lead (assuming
the lead is designed for a 13A load)?

I can't imagine why you assume extension leads are all 13A rated. I
assure you they're not. 10A leads get a 10A fuse, 5A leads get a 5A fuse
etc. Hardly a challenge.

Rather silly given the average person won't have a clue how much current
things take. And if, say, a 5 amp fuse blew would likely fit a 13 amp
one.

Safer to make them all 13 amp. Much as has happened with all leads these
days.

How can a 13 amp fuse make it"SAFER" than a 5 amp one?

Not the fuse, the flex / appliance.

If you design your product so that it is adequately protected by a 13A
fuse, then there is nothing the user can do to make it unsafe.

If you design it so that its requires lower fusing, then it means there
is a danger of it having inadequate fault protection if the user fits a
13A fuse without appreciating the implications.

I have wondered about this. If an appliance is designed to EU
specifications (with a different plug for UK models) does this mean it
is designed to operate safely with a 16 amp fuse given that Euro and
Schuko etc plugs are unfused and I understand circuits are fused at 16
amps.

Yup.

Its ok for the "plug in" appliance itself to require protection by a
lower rated fuse, but in which case it must include that fuse *in the
appliance* itself - it can't rely on there being a fused plug. (note
this may not apply for and appliance designed to be hard wired to a circuit)

To be saleable anywhere in Europe, the flex on the appliance will have
to get adequate fault protection when protected by the typical 16A
circuit breaker common in continental Europe. So this is usually done
by a combination of specifying a minimum flex conductor cross sectional
area, and also by specifying a maximum length of flex.



--
Cheers,

John.

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"Scott" wrote in message
...
On Mon, 21 Nov 2016 22:13:13 +0000, John Rumm
wrote:

On 21/11/2016 21:45, bert wrote:
In article , "Dave Plowman (News)"
writes
In article ,
wrote:
How do you chose the "correct" fuse for an extension lead (assuming
the lead is designed for a 13A load)?

I can't imagine why you assume extension leads are all 13A rated. I
assure you they're not. 10A leads get a 10A fuse, 5A leads get a 5A
fuse
etc. Hardly a challenge.

Rather silly given the average person won't have a clue how much
current
things take. And if, say, a 5 amp fuse blew would likely fit a 13 amp
one.

Safer to make them all 13 amp. Much as has happened with all leads
these
days.

How can a 13 amp fuse make it"SAFER" than a 5 amp one?

Not the fuse, the flex / appliance.

If you design your product so that it is adequately protected by a 13A
fuse, then there is nothing the user can do to make it unsafe.

If you design it so that its requires lower fusing, then it means there
is a danger of it having inadequate fault protection if the user fits a
13A fuse without appreciating the implications.

I have wondered about this. If an appliance is designed to EU
specifications (with a different plug for UK models) does this mean it
is designed to operate safely with a 16 amp fuse given that Euro and
Schuko etc plugs are unfused and I understand circuits are fused at 16
amps.

No they arent on that last.

On 23/09/2017 03:01, Rod Speed wrote:


"Scott" wrote in message
...
On Mon, 21 Nov 2016 22:13:13 +0000, John Rumm
wrote:

On 21/11/2016 21:45, bert wrote:
In article , "Dave Plowman (News)"
writes
In article ,
Â* wrote:
How do you chose the "correct" fuse for an extension lead (assuming
the lead is designed for a 13A load)?

I can't imagine why you assume extension leads are all 13A rated. I
assure you they're not. 10A leads get a 10A fuse, 5A leads get a
5A fuse
etc. Hardly a challenge.

Rather silly given the average person won't have a clue how much
current
things take. And if, say, a 5 amp fuse blew would likely fit a 13 amp
one.

Safer to make them all 13 amp. Much as has happened with all leads
these
days.

How can a 13 amp fuse make it"SAFER" than a 5 amp one?

Not the fuse, the flex / appliance.

If you design your product so that it is adequately protected by a 13A
fuse, then there is nothing the user can do to make it unsafe.

If you design it so that its requires lower fusing, then it means there
is a danger of it having inadequate fault protection if the user fits a
13A fuse without appreciating the implications.

I have wondered about this.Â* If an appliance is designed to EU
specifications (with a different plug for UK models) does this mean it
is designed to operate safely with a 16 amp fuse given that Euro and
Schuko etc plugs are unfused and I understand circuits are fused at 16
amps.

No they arent on that last.

??

Have you been on the grog?