On Tuesday, 7 January 2020 12:13:05 UTC, Tim+ wrote:
tabbypurr wrote:
On Monday, 6 January 2020 14:17:30 UTC, whisky-dave wrote:
On Monday, 6 January 2020 12:57:13 UTC, wrote:
On Monday, 6 January 2020 11:26:10 UTC, whisky-dave wrote:
The statement was what appliances NEED a fuse and not whether they
have one or not, there is a differnce there too.
If an appliance uses an "inherently short-circuit proof" mains transformer
for its power supply, it does not need any kind of fuse - not even an
over-temperature fuse inside the transformer.
That's what I assumed as not everything needs a fuse, light bulbs tend not
to have fuses. Then you have the difficulty of deciding what an appliance is.
Which for most mean something in a specific range of products.
The vast majority of which will end up being plugged into the mains and that
item will have a 3 pin plug on the end.
Filament lightbulbs have ballotini fuses
http://www.lamptech.co.uk/Documents/IN%20Fusing.htm
NT
Dont you mean €śalmost never have Ballotini fuses€ť? Ive never seen one.
Admittedly its a while since Ive squinted closely at a filament bulb but
Ive just dissected one and no sign of a Ballotini fuse.
I've seen many
Indeed, if youd read the link youd posted
I did
youd see that a) theyre
expensive
they aren't, they just cost more than a bit of thin wire
and b) reserved for lamps than cant accommodate the more normal
€śfuse wire€ť type fuse in the stem.
Some things are opinion, some things change over time. Yes of course there are lamps with cheaper fusing, and as the article says lamps with no fusing..
Ballotini Fusing
This is the safest and most reliable fuse type - but also the most
expensive. The fuse wire is encapsulated in a small glass tube filled with
tiny glass beads called Ballotini, named after Potters Ballotini, the
Italian producer. Should a secondary arc form between the broken pieces of
fuse wire, its heat will melt the glass beads to form an electrically
insulating barrier which contains and rapidly quenches the arc. It is so
efficient that only one fuse is required, but on account of their higher
price they are generally employed only in the more expensive special lamps,
or decorative lamps which are too small to be able to accommodate two
sufficiently long bare fuses (e.g. candle and globe lamps).
Tim
You may have noticed that candle and globe lamps are often not expensive.
NT