Purpose of fuse in televlision...

In alt.home.repair, on Sun, 13 Mar 2022 09:35:12 +0000, Jeff Layman
<jmlayman@invalid.invalid> wrote:

Retirednoguilt was kind enough to post
Power supply on ebay shows a fuse in the photo :
https://www.ebay.com/itm/Toshiba-40RV525U-Power-Supply-75013355-PK101V0830I-/263417775721?_trksid=p2349526.m4383.l4275.c3#viTabs_0
and that looks just like her power supply. --- Surprising since I had
found this video of someone repairing the PS on supposedly the same
model and the boards look entirely diffferen -- [Insert url here]

(what url did you forget to insert?!)

I was going to find the url before posting. Failing that I tried just
now.

Someone messed with my Firefox and made Bing the default search engine!!
I sure didn\'t do that.

So I thought if I went back to google I\'d find it. It was the second or
third hit when I first looked, searching on the TV model number. Now I
can\'t find it at all. I thought it int eresting becaue the board didn\'t
look at all like the one in the ebay ad, and maybe someone wrote him or
he noticed he had the wrong model number and he changed it, so I can\'t
find it. Who knows? It was the wrong video anyhow.
 
On 3/13/2022 7:46 AM, micky wrote:
In alt.home.repair, on Sun, 13 Mar 2022 09:35:12 +0000, Jeff Layman
jmlayman@invalid.invalid> wrote:

On 13/03/2022 05:52, micky wrote:
In alt.home.repair, on Sat, 12 Mar 2022 11:54:18 -0800, Bob F
bobnospam@gmail.com> wrote:

On 3/12/2022 10:55 AM, micky wrote:

(snip)

This seems very important. If there is one that\'s shorted, it will just
blow the fuse over and over, and if I\'ve bypassed the fuse....would that
allow enough current to start a fire?

Retirednoguilt was kind enough to post
Power supply on ebay shows a fuse in the photo :
https://www.ebay.com/itm/Toshiba-40RV525U-Power-Supply-75013355-PK101V0830I-/263417775721?_trksid=p2349526.m4383.l4275.c3#viTabs_0
and that looks just like her power supply. --- Surprising since I had
found this video of someone repairing the PS on supposedly the same
model and the boards look entirely diffferen -- [Insert url here]

(what url did you forget to insert?!)

Who knows! With all the radiation I\'ve gotten ever since I used that
off-brand fuse, I can\'t tell my right hand from my right hand.

Did you not read the warning above the fuse on that PCB?

No. Warnings are for grown-ups.

\"CAUTION: For continued protection against risk of fire replace only
with same type and rating of fuse\". I don\'t think it could be any clearer.

Out of interest, is it usual in the US to spec a 240V fuse for use with
a 120V supply?

Most fuses go up to 250, don\'t they?

I can\'t remember ever seeing a \"120V\" fuse. The basic configuration of
old fashioned fuses will handle 250V fine. How/why would they make them
\"120V\" fuses.
 
On 3/12/2022 9:52 PM, micky wrote:
In alt.home.repair, on Sat, 12 Mar 2022 11:54:18 -0800, Bob F
bobnospam@gmail.com> wrote:

On 3/12/2022 10:55 AM, micky wrote:
I took apart the television I\'ve posted about and there is a fuse on the
power supply board and it\'s blown. It was blown (and the home circuit
breaker was tripped at the same time it iseems) when a helpful neighbor
plugged the 110v tv straight into 220.

What is the purpose of the fuse: To keep a short circuit in the power
supply (or other part of the tv) from pulling too much current, melting
the wire\'s insulation, and starting a fire?

Or the opposite, to protect the TV
from surges.

It will be hard to find another fuse. It\'s a small size ceramic fuse.
I can post the size after I f ind a lamp and a magnifying glass, but
it\'s probably 2 or 3 amps, right? (Are all ceramic fuses slo-blo?)

If the purpose of the fuse is only to protect the tv, I\'m willing to
take the risk, wrap the fuse in tinfoil and put it back together.

If it\'s to avoid a fire, then this is a 110v tv in a 220 volt world,
supplied by a step-down transformer of limited amperage. 500 watts. (It
gives the same wattage for both directions.) Surely even a cold short
in the tv when the maxiumum supplied power is I guess about 5 amps would
not be anywhere near enough to start a fire.

Right?

The other possibility is to wrap the fuse in foil, decide if it works or
not, and leave here (where it is too cold for me and too rainy) and come
back after I buy the right fuse in a city. What are the odds it will
fail in the next 3 week? That requires putting the tv back togehter an
extra time, but that\'s not so bad.

There could be a voltage limiter, like a MOV just past that fuse that
shorts out to blow the fuse, thus keeping surge voltage from frying the
TV. Such a device may need to be replaced also to retain that
protection, or, if shorted, it would have to be disconnected.

This seems very important. If there is one that\'s shorted, it will just
blow the fuse over and over, and if I\'ve bypassed the fuse....would that
allow enough current to start a fire?

The board has a fee parts that might be a MOV.
They are labeled CY101..., TH101..., UA101 and CP101. There is only
one of the last two.
Are any of these usual abbreviation for a MOV? I\'ve been looking
online for a list of abbreviations that includes these, no luck so far,
quicker to ask you, Bob (and others).

Retirednoguilt was kind enough to post
Power supply on ebay shows a fuse in the photo :
https://www.ebay.com/itm/Toshiba-40RV525U-Power-Supply-75013355-PK101V0830I-/263417775721?_trksid=p2349526.m4383.l4275.c3#viTabs_0
and that looks just like her power supply. --- Surprising since I had
found this video of someone repairing the PS on supposedly the same
model and the boards look entirely diffferen -- [Insert url here]

I\'m the second or third person she\'s had look at it. It\'s too big and
heavy to take to a shop, so if I bypass the fuse and fail to note a
shorted MOV and it gets worse, I think she will just take her loss and
buy one.

If the fuse did its job fast enough, the MOV, if any, may be fine.

A little light reading
https://www.homemade-circuits.com/how-to-select-mov/

References to previous thread. The TV has HDMI input (3 interfaces!),
but when she lived in Baltimore she was streaming from Amazon, and I
think that was her current plan. Although I don\'t understand how. The
manual says \"INPUT — Repeatedly press to change the source you are
viewing (ANT/CABLE, VIDEO 1, VIDEO 2, ColorStream
HD1, ColorStream HD2, HDMI 1, HDMI 2, HDMI 3, PC).\"

Colorstream is their name for separate red, blue, whatever color input.
Component! That\'s it. She can\'t use that.

Video1 AND 2 are composite, she can\'t use that.

Smart TVs can stream directly through their WiFi or ethernet cable
connector. A streaming box, like an Amazon Fire TV, can be plugged into
any HDMI input of older TVs to do the same.

Used 50\" TV\'s are easy to find these days for $50, or often free in my
local Craigslist. I picked up a 55\" 4K TV with just a little screen burn
for $75 a few weeks ago.

PC IN — For use when connecting a personal computer. When she lived in
Baltimore her PC was in another room and I don\'t think there was a wire
connecting them. I\'ve written her son to try to find out what she is
talking about.
 
On 3/13/2022 6:37 AM, micky wrote:
Ok, guys, I jumpered the fuse holder with a store-bought 10\" jumper wire
and got a big spark (even before I tried to turn the tv on. I guess I
should have anticipated that.)

I thought that was bad until I thought, Well, it uses almost 8 amps and
maybe the alligator clips didn\'t make a good connection.

So used all three jumper wires and this time no spark, just smoke. :)

From one of the diodes, based on the brown spot next to it and the
swollen diode.

Plus the alligator clips at one end of two of the jumper wires fell off!

So now it\'s on to a new board.

The board is discontinued of course, but there are lots for sale at
various places, all about 40 dollars. Whether they are new,
\"reconditioned\" or used, it\'s okay by me.

The part number is Toshiba PK101V0830I

But what would be great is to find the 220v version of this. So how
would I find what the part number is for the 220 volt version of this.

I wrote Toshiba to ask what the partnumber would be for 220v, but I
think I wrote Toshiba USA. I can call Toshiba in the US Monday at
8AM. Will they know or should I call some European repairman? I
haven\'t found a tech support page for anywhere in Europe yet. It looks
like I have but then the page is about all of Toshiba, not just tvs, not
just consumer goods,

Would Toshiba use the same tv model# 40RV525U for its 220volt model? I
doubt it, and I can\'t guess what it would be.

What should I do next? (Helpful answers only, please.)

Buy a used TV.

In alt.home.repair, on Sat, 12 Mar 2022 20:55:09 +0200, micky
NONONOmisc07@fmguy.com> wrote:

I took apart the television I\'ve posted about and there is a fuse on the
power supply board and it\'s blown. It was blown (and the home circuit
breaker was tripped at the same time it iseems) when a helpful neighbor
plugged the 110v tv straight into 220.

What is the purpose of the fuse: To keep a short circuit in the power
supply (or other part of the tv) from pulling too much current, melting
the wire\'s insulation, and starting a fire?

Or the opposite, to protect the TV
from surges.

It will be hard to find another fuse. It\'s a small size ceramic fuse.
I can post the size after I f ind a lamp and a magnifying glass, but
it\'s probably 2 or 3 amps, right? (Are all ceramic fuses slo-blo?)

If the purpose of the fuse is only to protect the tv, I\'m willing to
take the risk, wrap the fuse in tinfoil and put it back together.

If it\'s to avoid a fire, then this is a 110v tv in a 220 volt world,
supplied by a step-down transformer of limited amperage. 500 watts. (It
gives the same wattage for both directions.) Surely even a cold short
in the tv when the maxiumum supplied power is I guess about 5 amps would
not be anywhere near enough to start a fire.

Right?

The other possibility is to wrap the fuse in foil, decide if it works or
not, and leave here (where it is too cold for me and too rainy) and come
back after I buy the right fuse in a city. What are the odds it will
fail in the next 3 week? That requires putting the tv back togehter an
extra time, but that\'s not so bad.
































We are 50 miles from nowhere down a rainy winding road.
 
In article <t0l3t2$ql3$1@dont-email.me>, bobnospam@gmail.com says...
On 3/13/2022 7:46 AM, micky wrote:
In alt.home.repair, on Sun, 13 Mar 2022 09:35:12 +0000, Jeff Layman
jmlayman@invalid.invalid> wrote:

On 13/03/2022 05:52, micky wrote:
In alt.home.repair, on Sat, 12 Mar 2022 11:54:18 -0800, Bob F
bobnospam@gmail.com> wrote:

On 3/12/2022 10:55 AM, micky wrote:

(snip)

This seems very important. If there is one that\'s shorted, it will just
blow the fuse over and over, and if I\'ve bypassed the fuse....would that
allow enough current to start a fire?

Retirednoguilt was kind enough to post
Power supply on ebay shows a fuse in the photo :
https://www.ebay.com/itm/Toshiba-40RV525U-Power-Supply-75013355-PK101V0830I-/263417775721?_trksid=p2349526.m4383.l4275.c3#viTabs_0
and that looks just like her power supply. --- Surprising since I had
found this video of someone repairing the PS on supposedly the same
model and the boards look entirely diffferen -- [Insert url here]

(what url did you forget to insert?!)

Who knows! With all the radiation I\'ve gotten ever since I used that
off-brand fuse, I can\'t tell my right hand from my right hand.

Did you not read the warning above the fuse on that PCB?

No. Warnings are for grown-ups.

\"CAUTION: For continued protection against risk of fire replace only
with same type and rating of fuse\". I don\'t think it could be any clearer.

Out of interest, is it usual in the US to spec a 240V fuse for use with
a 120V supply?

Most fuses go up to 250, don\'t they?

I can\'t remember ever seeing a \"120V\" fuse. The basic configuration of
old fashioned fuses will handle 250V fine. How/why would they make them
\"120V\" fuses.

Surely the fuse would be identical, just the labelling changed for the
benefit of people who did not know what it meant anyway...
 
In alt.home.repair, on Sun, 13 Mar 2022 09:07:50 -0700, Bob F
<bobnospam@gmail.com> wrote:

On 3/12/2022 9:52 PM, micky wrote:
In alt.home.repair, on Sat, 12 Mar 2022 11:54:18 -0800, Bob F
bobnospam@gmail.com> wrote:

On 3/12/2022 10:55 AM, micky wrote:
I took apart the television I\'ve posted about and there is a fuse on the
power supply board and it\'s blown. It was blown (and the home circuit
breaker was tripped at the same time it iseems) when a helpful neighbor
plugged the 110v tv straight into 220.

What is the purpose of the fuse: To keep a short circuit in the power
supply (or other part of the tv) from pulling too much current, melting
the wire\'s insulation, and starting a fire?

Or the opposite, to protect the TV
from surges.

It will be hard to find another fuse. It\'s a small size ceramic fuse.
I can post the size after I f ind a lamp and a magnifying glass, but
it\'s probably 2 or 3 amps, right? (Are all ceramic fuses slo-blo?)

If the purpose of the fuse is only to protect the tv, I\'m willing to
take the risk, wrap the fuse in tinfoil and put it back together.

If it\'s to avoid a fire, then this is a 110v tv in a 220 volt world,
supplied by a step-down transformer of limited amperage. 500 watts. (It
gives the same wattage for both directions.) Surely even a cold short
in the tv when the maxiumum supplied power is I guess about 5 amps would
not be anywhere near enough to start a fire.

Right?

The other possibility is to wrap the fuse in foil, decide if it works or
not, and leave here (where it is too cold for me and too rainy) and come
back after I buy the right fuse in a city. What are the odds it will
fail in the next 3 week? That requires putting the tv back togehter an
extra time, but that\'s not so bad.

There could be a voltage limiter, like a MOV just past that fuse that
shorts out to blow the fuse, thus keeping surge voltage from frying the
TV. Such a device may need to be replaced also to retain that
protection, or, if shorted, it would have to be disconnected.

This seems very important. If there is one that\'s shorted, it will just
blow the fuse over and over, and if I\'ve bypassed the fuse....would that
allow enough current to start a fire?

The board has a fee parts that might be a MOV.
They are labeled CY101..., TH101..., UA101 and CP101. There is only
one of the last two.
Are any of these usual abbreviation for a MOV? I\'ve been looking
online for a list of abbreviations that includes these, no luck so far,
quicker to ask you, Bob (and others).

Retirednoguilt was kind enough to post
Power supply on ebay shows a fuse in the photo :
https://www.ebay.com/itm/Toshiba-40RV525U-Power-Supply-75013355-PK101V0830I-/263417775721?_trksid=p2349526.m4383.l4275.c3#viTabs_0
and that looks just like her power supply. --- Surprising since I had
found this video of someone repairing the PS on supposedly the same
model and the boards look entirely diffferen -- [Insert url here]

I\'m the second or third person she\'s had look at it. It\'s too big and
heavy to take to a shop, so if I bypass the fuse and fail to note a
shorted MOV and it gets worse, I think she will just take her loss and
buy one.

If the fuse did its job fast enough, the MOV, if any, may be fine.

I guess it didn\'t. I might not have said this because I distrust some
of the reports I\'ve gotten but did I mention that the whole house went
dark when this first happened? So I guess it wasn\'t fast enough.
A little light reading
https://www.homemade-circuits.com/how-to-select-mov/

Bedtime.
References to previous thread. The TV has HDMI input (3 interfaces!),
but when she lived in Baltimore she was streaming from Amazon, and I
think that was her current plan. Although I don\'t understand how. The
manual says \"INPUT — Repeatedly press to change the source you are
viewing (ANT/CABLE, VIDEO 1, VIDEO 2, ColorStream
HD1, ColorStream HD2, HDMI 1, HDMI 2, HDMI 3, PC).\"

Colorstream is their name for separate red, blue, whatever color input.
Component! That\'s it. She can\'t use that.

Video1 AND 2 are composite, she can\'t use that.

Smart TVs can stream directly through their WiFi or ethernet cable
connector. A streaming box, like an Amazon Fire TV, can be plugged into
any HDMI input of older TVs to do the same.

She claimed she needed no box. I\'ll ask her son.

Used 50\" TV\'s are easy to find these days for $50, or often free in my
local Craigslist. I picked up a 55\" 4K TV with just a little screen burn
for $75 a few weeks ago.

I looked for thrift shops but I haven\'t looked on Craiglist. That\'s
where I got an apartment one year, but this year the closest roommates
wanted were 100\'s of miles away. Maybe covid is responsible somehow.
PC IN — For use when connecting a personal computer. When she lived in
Baltimore her PC was in another room and I don\'t think there was a wire
connecting them. I\'ve written her son to try to find out what she is
talking about.
 
In alt.home.repair, on Sat, 12 Mar 2022 19:58:22 -0000, Mike Coon
<gravity@mjcoon.plus.com> wrote:

In article <5esp2hpfn7o6snpjv8fr9tr1b01v6jvk0l@4ax.com>, NONONOmisc07
@fmguy.com says...

You cannot mean 40 amps, surely? Even at only 110 volts that is still
quite a powerful heater! 40 inches, perhaps?

yes 40 inches!!
 
On 3/13/2022 10:46 AM, micky wrote:
In alt.home.repair, on Sun, 13 Mar 2022 09:07:50 -0700, Bob F
bobnospam@gmail.com> wrote:

On 3/12/2022 9:52 PM, micky wrote:
In alt.home.repair, on Sat, 12 Mar 2022 11:54:18 -0800, Bob F
bobnospam@gmail.com> wrote:

On 3/12/2022 10:55 AM, micky wrote:
I took apart the television I\'ve posted about and there is a fuse on the
power supply board and it\'s blown. It was blown (and the home circuit
breaker was tripped at the same time it iseems) when a helpful neighbor
plugged the 110v tv straight into 220.

What is the purpose of the fuse: To keep a short circuit in the power
supply (or other part of the tv) from pulling too much current, melting
the wire\'s insulation, and starting a fire?

Or the opposite, to protect the TV
from surges.

It will be hard to find another fuse. It\'s a small size ceramic fuse.
I can post the size after I f ind a lamp and a magnifying glass, but
it\'s probably 2 or 3 amps, right? (Are all ceramic fuses slo-blo?)

If the purpose of the fuse is only to protect the tv, I\'m willing to
take the risk, wrap the fuse in tinfoil and put it back together.

If it\'s to avoid a fire, then this is a 110v tv in a 220 volt world,
supplied by a step-down transformer of limited amperage. 500 watts. (It
gives the same wattage for both directions.) Surely even a cold short
in the tv when the maxiumum supplied power is I guess about 5 amps would
not be anywhere near enough to start a fire.

Right?

The other possibility is to wrap the fuse in foil, decide if it works or
not, and leave here (where it is too cold for me and too rainy) and come
back after I buy the right fuse in a city. What are the odds it will
fail in the next 3 week? That requires putting the tv back togehter an
extra time, but that\'s not so bad.

There could be a voltage limiter, like a MOV just past that fuse that
shorts out to blow the fuse, thus keeping surge voltage from frying the
TV. Such a device may need to be replaced also to retain that
protection, or, if shorted, it would have to be disconnected.

This seems very important. If there is one that\'s shorted, it will just
blow the fuse over and over, and if I\'ve bypassed the fuse....would that
allow enough current to start a fire?

The board has a fee parts that might be a MOV.
They are labeled CY101..., TH101..., UA101 and CP101. There is only
one of the last two.
Are any of these usual abbreviation for a MOV? I\'ve been looking
online for a list of abbreviations that includes these, no luck so far,
quicker to ask you, Bob (and others).

Retirednoguilt was kind enough to post
Power supply on ebay shows a fuse in the photo :
https://www.ebay.com/itm/Toshiba-40RV525U-Power-Supply-75013355-PK101V0830I-/263417775721?_trksid=p2349526.m4383.l4275.c3#viTabs_0
and that looks just like her power supply. --- Surprising since I had
found this video of someone repairing the PS on supposedly the same
model and the boards look entirely diffferen -- [Insert url here]

I\'m the second or third person she\'s had look at it. It\'s too big and
heavy to take to a shop, so if I bypass the fuse and fail to note a
shorted MOV and it gets worse, I think she will just take her loss and
buy one.

If the fuse did its job fast enough, the MOV, if any, may be fine.

I guess it didn\'t. I might not have said this because I distrust some
of the reports I\'ve gotten but did I mention that the whole house went
dark when this first happened? So I guess it wasn\'t fast enough.

Knowing that, It is probably time to write that TV off. Who knows where
in the TV got too much voltage?



A little light reading
https://www.homemade-circuits.com/how-to-select-mov/

Bedtime.


References to previous thread. The TV has HDMI input (3 interfaces!),
but when she lived in Baltimore she was streaming from Amazon, and I
think that was her current plan. Although I don\'t understand how. The
manual says \"INPUT — Repeatedly press to change the source you are
viewing (ANT/CABLE, VIDEO 1, VIDEO 2, ColorStream
HD1, ColorStream HD2, HDMI 1, HDMI 2, HDMI 3, PC).\"

Colorstream is their name for separate red, blue, whatever color input.
Component! That\'s it. She can\'t use that.

Video1 AND 2 are composite, she can\'t use that.

Smart TVs can stream directly through their WiFi or ethernet cable
connector. A streaming box, like an Amazon Fire TV, can be plugged into
any HDMI input of older TVs to do the same.

She claimed she needed no box. I\'ll ask her son.

Used 50\" TV\'s are easy to find these days for $50, or often free in my
local Craigslist. I picked up a 55\" 4K TV with just a little screen burn
for $75 a few weeks ago.

I looked for thrift shops but I haven\'t looked on Craiglist. That\'s
where I got an apartment one year, but this year the closest roommates
wanted were 100\'s of miles away. Maybe covid is responsible somehow.


PC IN — For use when connecting a personal computer. When she lived in
Baltimore her PC was in another room and I don\'t think there was a wire
connecting them. I\'ve written her son to try to find out what she is
talking about.
 
On 13/03/2022 18:02, micky wrote:
In alt.home.repair, on Sat, 12 Mar 2022 19:58:22 -0000, Mike Coon
gravity@mjcoon.plus.com> wrote:

In article <5esp2hpfn7o6snpjv8fr9tr1b01v6jvk0l@4ax.com>, NONONOmisc07
@fmguy.com says...

You cannot mean 40 amps, surely? Even at only 110 volts that is still
quite a powerful heater! 40 inches, perhaps?

yes 40 inches!!

Hi Micky,

Twice the voltage in something not prepared for it is a crap shoot to
fix. And sounds like you have taken a US television abroad? Heap of pain
with standards and frequencies?

As others have posted, yeah - buy/bag a used TV

Some folks are throwing out their perfectly good \'old\' 4 yr old LCD TVs
the same way some of them throw out their mobile phones.

It\'s the apps. They have to have their apps.

It\'s a TV!

--
Adrian C
 
Adrian Caspersz wrote:
==================
Hi Micky,

Twice the voltage in something not prepared for it is a crap shoot to
fix.

** Certainly is with SMPSs.

But when iron transformers ruled, it mostly only blew a supply fuse.
Such transformers draw a HUGE current when double voltaged and save the circuitry.


> And sounds like you have taken a US television abroad?

** Stupid folk do things like that.


..... Phil
 
On Sun, 13 Mar 2022 09:07:50 -0700, Bob F <bobnospam@gmail.com> wrote:

Used 50\" TV\'s are easy to find these days for $50, or often free in my
local Craigslist. I picked up a 55\" 4K TV with just a little screen burn
for $75 a few weeks ago.

It\'s amazing how just a tiny burn becomes a distraction. I put up with
a barely visible dot on a TV for about a year because I couldn\'t get
out to buy a new one. Eventually a friend bought me a new one because
she was sick of me moaning about the dot!
 
On Sunday, March 13, 2022 at 1:35:17 AM UTC-8, Jeff Layman wrote:

Out of interest, is it usual in the US to spec a 240V fuse for use with
a 120V supply?

Yes, it is. The possibility of a \'floating neutral\' means that a 240V input
from a nominal 120V socket is a (relatively) common kind of home wiring failure.
 
I think \'Micky\' uses a random generator to bring up all these questions.
He doesn\'t even want an answer. He just wants to roil up the newsgroups.

This isn\'t the only newsgroup he does this random question generation on.
I think he does it for fun but we\'d have to ask him why he does it.
 
On Thursday, March 17, 2022 at 10:03:24 AM UTC-4, YK wrote:
I think \'Micky\' uses a random generator to bring up all these questions.
He doesn\'t even want an answer. He just wants to roil up the newsgroups.

This isn\'t the only newsgroup he does this random question generation on.
I think he does it for fun but we\'d have to ask him why he does it.

He\'d be better off then spamming Quora, who *encourages* this type of inane questioning and will actually pay you if you can pump enough questions into their site.
 
On Thursday, March 17, 2022 at 10:03:24 AM UTC-4, YK wrote:
I think \'Micky\' uses a random generator to bring up all these questions.
He doesn\'t even want an answer. He just wants to roil up the newsgroups.

This isn\'t the only newsgroup he does this random question generation on.
I think he does it for fun but we\'d have to ask him why he does it.

The fact that he/she/they/them/it is an idiot/troll/an AI program was apparent from his first few posts. No one can be that stupid, well then again, there are exceptions.
Ignore him/her/they/them/it and (hopefully) it will go away.
J
 
On Saturday, March 12, 2022 at 12:55:16 PM UTC-6, micky wrote:
I took apart the television I\'ve posted about and there is a fuse on the
power supply board and it\'s blown. It was blown (and the home circuit
breaker was tripped at the same time it iseems) when a helpful neighbor
plugged the 110v tv straight into 220.

What is the purpose of the fuse: To keep a short circuit in the power
supply (or other part of the tv) from pulling too much current, melting
the wire\'s insulation, and starting a fire?

Or the opposite, to protect the TV
from surges.

It will be hard to find another fuse. It\'s a small size ceramic fuse.
I can post the size after I f ind a lamp and a magnifying glass, but
it\'s probably 2 or 3 amps, right? (Are all ceramic fuses slo-blo?)

If the purpose of the fuse is only to protect the tv, I\'m willing to
take the risk, wrap the fuse in tinfoil and put it back together.

If it\'s to avoid a fire, then this is a 110v tv in a 220 volt world,
supplied by a step-down transformer of limited amperage. 500 watts. (It
gives the same wattage for both directions.) Surely even a cold short
in the tv when the maxiumum supplied power is I guess about 5 amps would
not be anywhere near enough to start a fire.

Right?

The other possibility is to wrap the fuse in foil, decide if it works or
not, and leave here (where it is too cold for me and too rainy) and come
back after I buy the right fuse in a city. What are the odds it will
fail in the next 3 week? That requires putting the tv back togehter an
extra time, but that\'s not so bad.
































We are 50 miles from nowhere down a rainy winding road.

The purpose of a fuse is for protection of the consumer (or consumer\'s house)
in the event of any electrical failure beyond the comprehension of the consumer.
The fuse is designed to open up even with the slightest of problems. Safety first.
The circuits start out as AC (alternating current) power and have to go through
a few power conversions. There is AC to DC conversion and AC to AC conversion.
In your case, it sounds like you had an over-voltage
condition (a form of overload on the input power, or a form of a power surge).
From what you tell the board or forum, more than likely
it is a one-off situation. I would spend the $3 on the replacement fuse (and never
use tin foil or a penny for a number of various reasons, some of them obvious).

Other reasons why fuses blow is because of short circuits, failed components,
overcurrent conditions, and overvoltage conditions. Seems like you had an overvoltage
condition (which is a relatively minor problem, based on what you said) versus the other
reasons fuses blow. This is a small part of some of the failures found in electronics.
 
The purpose of a fuse is for protection of the consumer (or consumer\'s house)
in the event of any electrical failure beyond the comprehension of the consumer.
The fuse is designed to open up even with the slightest of problems. Safety first.
The circuits start out as AC (alternating current) power and have to go through
a few power conversions. There is AC to DC conversion and AC to AC conversion.
In your case, it sounds like you had an over-voltage
condition (a form of overload on the input power, or a form of a power surge).

I am not sure what you do for either a hobby, business or living of any nature. What is clear is that your knowledge of fuses is a mile wide, but only an inch deep.

Some basics:
a) Fuses do age. and fuses that run even reasonably close to their rating age rather quickly. Dozens of months, not dozens of years.
b) Fuses come in many types - most basic are \"Normal\", \"Slow Blow\" and \"Time Delay\", not to be confused with Slow Blow. Within each basic category are sub-sets:

\"Normal\" also comes in Fast-Blow and Ultra-Fast Blow.
\"Slow Blow\" also comes in Very-Slow-Blow - You might see these types on Kilns and other very heavy resistance-only loads where equipment failure is very rare, and the fuses are rated against nuisance failures.
\"Time Delay\", AKA Dual-Element Fuses can handle an initial surge, then revert to \'standard\' or \'fast\' behavior. Mostly seen on motor-loads, but useful for tube equipment, as cold filaments have very low resistance. With these fuses, the amount and time of the surge tolerated varies.

The OP does not understand the nature of the fuse in the Device. Just as you do not understand the \'which fuse\' question. However, it is clear that the fuse failed properly - not from age - and that there is something else going on. 8 amps! that is a lot of current into even a very large-screen TV. Our vintage, very large plasma TV pulls half of that. So, whatever is going on is serious.

As to bypassing fuses - DO SO FIRST IF ONE MUST across either (an) incandescent lamp(s) of some wattage such that one might predict how bright it should be, 8 amps @ 110 VAC is 880 watts - start with 200 watts and see if that goes to full brightness. Unless the screen is huge, I cannot imagine that, as \"Book\" on a 60\" LED is 200 watts. \"Book\" on a similar Plasma is 500 watts. But, NEVER with a jumper. Then again, is the OP\'s fuse at line-level, or down-line? Hmmmm...

I have a little outboard fuse block that I will jumper into a piece of equipment so as to be able to do tests - but there is STILL a fuse involved.
 

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