House of Horrors

In message , Graham.
writes

On the subject of plug fuses,
Most of the equipment I install is powered by an IEC
13A plug (kettle lead)
No it isn't, a kettle lead is a "Hot Condition" socket, and has a cutout
in it. The leads you mean won't fit into a kettle.


Glad to see you're awake at the back. I should of course used
quotes or a "so-called" qualification rather than parentheses.

One of my pet hates!

Remember those round kettle plugs that auto-ejected if the
kettle boiled dry?

Oh yes. God I'm getting old....
--
Kevin Seal
F800ST
{kevin at the hyphen seal hyphen house dot freeserve dot co dot uk}

In article , Graham.
writes

On the subject of plug fuses,
Most of the equipment I install is powered by an IEC
13A plug (kettle lead)
No it isn't, a kettle lead is a "Hot Condition" socket, and has a cutout
in it. The leads you mean won't fit into a kettle.


Glad to see you're awake at the back. I should of course used
quotes or a "so-called" qualification rather than parentheses.

Remember those round kettle plugs that auto-ejected if the
kettle boiled dry?

I almost went through the ceiling the day a colleagues kettle did that,
it put me off electric kettles for a l-o-n-g time, with 40 and 100kV
test rigs in the adjacent high energy test room I thought something far
nastier than a kettle was involved.

--
Ian G8ILZ
There are always two people in every pictu the photographer and the viewer.
~Ansel Adams

"Graham." wrote in message
...

Remember those round kettle plugs that auto-ejected if the
kettle boiled dry?

Those that jumped out and fell in the sink?

Bill

In article , Adrian A
writes
Max Demian wrote:
"Peter Thomas" wrote in
message

I used to see a lot of this stuff. What happens is the primary
winding of the miniature power transformer gets shorted turns
and gets very hot. Even in this condition the amplifier can
continue to work, until the fuse blows. I would expect the
internal protection to kick in first of course, the plug
fuse blowing suggests catastrophic failure.

It's worth noting that the vast majority of electrical items in the
home (but not mine) have plug tops that are equipped with 13A fuses -
coz it says on the plug 13A !!

Well a 13A fuse will blow in the event of a dead short in the lead or
the primary of the mains transformer, and a 3A one *won't* blow in
the event of a more subtle fault such as a short in the output from
the mains transformer - so I reckon 13A for everything provides as
much practical protection as a 3A, even for low consumption
appliances.

What absolute nonsense! If you put a 13amp fuse in most appliences then the
flex becomes the fuse.



Have you ever looked at the size of the wire in a 13 amp fuse?....
--
Tony Sayer

In article , "Dave Plowman (News)"
writes
In article ,
Prometheus wrote:
Fuses do fail with age; I have had a few which have failed after many
years operation, when I check the current consumption I find it to be as
expected, so I replace the failed fuse and the kit continues to work.

That can apply to a fuse working near its rated value - it continually
expands and contracts as it's powered up and down etc. A 3 amp fuse
feeding a DA might as well be a lump of solid brass as regards heating
effect.

All very true, but there should be a much lower rated protection device
in the DA (or its PSU), a 'protection' that would allow about 700 W to
be dissipated under a fault condition is no protection at all.

--
Ian G8ILZ
There are always two people in every pictu the photographer and the viewer.
~Ansel Adams

"Bill Wright" wrote in message

"Graham." wrote in message
...

Remember those round kettle plugs that auto-ejected if the
kettle boiled dry?

Those that jumped out and fell in the sink?

Nice idea, Bill, but have you known that to happen in actuality?

--
Max Demian

"tony sayer" wrote in message

In article , Adrian A
writes
Max Demian wrote:
"Peter Thomas" wrote in
message

I used to see a lot of this stuff. What happens is the primary
winding of the miniature power transformer gets shorted turns
and gets very hot. Even in this condition the amplifier can
continue to work, until the fuse blows. I would expect the
internal protection to kick in first of course, the plug
fuse blowing suggests catastrophic failure.

It's worth noting that the vast majority of electrical items in the
home (but not mine) have plug tops that are equipped with 13A
fuses - coz it says on the plug 13A !!

Well a 13A fuse will blow in the event of a dead short in the lead
or the primary of the mains transformer, and a 3A one *won't* blow
in the event of a more subtle fault such as a short in the output
from the mains transformer - so I reckon 13A for everything
provides as much practical protection as a 3A, even for low
consumption appliances.

What absolute nonsense! If you put a 13amp fuse in most appliences
then the flex becomes the fuse.

Have you ever looked at the size of the wire in a 13 amp fuse?....

Moot as the fuse is likely to be made of a different metal than a mains
conductor.

--
Max Demian

In article , Max Demian
writes
"tony sayer" wrote in message

In article , Adrian A
writes
Max Demian wrote:
"Peter Thomas" wrote in
message

I used to see a lot of this stuff. What happens is the primary
winding of the miniature power transformer gets shorted turns
and gets very hot. Even in this condition the amplifier can
continue to work, until the fuse blows. I would expect the
internal protection to kick in first of course, the plug
fuse blowing suggests catastrophic failure.

It's worth noting that the vast majority of electrical items in the
home (but not mine) have plug tops that are equipped with 13A
fuses - coz it says on the plug 13A !!

Well a 13A fuse will blow in the event of a dead short in the lead
or the primary of the mains transformer, and a 3A one *won't* blow
in the event of a more subtle fault such as a short in the output
from the mains transformer - so I reckon 13A for everything
provides as much practical protection as a 3A, even for low
consumption appliances.

What absolute nonsense! If you put a 13amp fuse in most appliences
then the flex becomes the fuse.

Have you ever looked at the size of the wire in a 13 amp fuse?....

Moot as the fuse is likely to be made of a different metal than a mains
conductor.

And what sort of metal would that be then, the fuse that is?..
--
Tony Sayer

"Max Demian" wrote in message
...

Moot as the fuse is likely to be made of a different metal than a mains
conductor.

Duh!

It will be a metal with a higher resistance than copper, not lower, and it's
*still* thinner even then.

--

Brian Gregory. (In the UK)

To email me remove the letter vee.

In article ,
Prometheus wrote:
That can apply to a fuse working near its rated value - it continually
expands and contracts as it's powered up and down etc. A 3 amp fuse
feeding a DA might as well be a lump of solid brass as regards heating
effect.

All very true, but there should be a much lower rated protection device
in the DA (or its PSU), a 'protection' that would allow about 700 W to
be dissipated under a fault condition is no protection at all.

Like I said, unless it's ancient or has a separate fuse, there is likely a
thermal fuse built into the transformer.

--
*Never slap a man who's chewing tobacco *

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