Hi,
I have a wall wort that is 120v. In and 24VAC out that stopped working
the
other day...
I pulled the caseing apart and found that all it is,is a small
transformer,
so I checked continuity on the secondary side and it checked good.
I checked the continuity on the primary and it showed open so I
carefully
started to disect that side and across the turns was a small device I
just found
out through Google is a Thermal Cutoff(It is marked "Aupo A4-1A
130*c").

I found a site that said to test the thermal cutoff all that is needed
is to
check for continuity and if open it is no good.
Well it has no continuity so I am assuming it is bad,but my question
is...

Is the Thermal Cutoff really needed?
The wall wort goes to one of those real small fountains that make fog
and lights that change color.

Any help would be greatly Appreciated
Thank You

Is the Thermal Cutoff really needed?

Not if your fire insurance is paid up.

wrote:
Is the Thermal Cutoff really needed?

It blew out once, likely because of overtemperature. Bypass it and next time
the blowout might not be something quiet and flameless.

--
God help us all,
The next President of the United States will be a liberal.

"Charles" writes:

Is the Thermal Cutoff really needed?

Not if your fire insurance is paid up.

Even then. Since if the insurance inspector finds that the wall adapter
was tampered with, you better have a good lawyer.

It's only a $2 part. Sounds like 130 degC, 1 A.

If it goes again, the transformer is overheating either because there
are some shorted turns in the transformer or the load is too high.

Or, just get a new wall adapter.

NBVER defeat a safety device except possibly for brief testing.

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"Sam Goldwasser" wrote in message
...
"Charles" writes:

Is the Thermal Cutoff really needed?

Not if your fire insurance is paid up.

Even then. Since if the insurance inspector finds that the wall adapter
was tampered with, you better have a good lawyer.

It's only a $2 part. Sounds like 130 degC, 1 A.

If it goes again, the transformer is overheating either because there
are some shorted turns in the transformer or the load is too high.

Or, just get a new wall adapter.

NEVER defeat a safety device except possibly for brief testing.


Absolutely agreed. Do not bypass this essential protection device

Arfa

Doh,Thanks for catching that everybody.
I don't know why it is,but I seem to always pass over the most simple
and obvious things when it comes to this stuff. I'm sure if I would
have stopped and thought about it and let everything marinate awhile I
would have figured out what a stupid idea/question that was.

Thanks again guys,its most Appreciated

"Sam Goldwasser" wrote:
"Charles" writes:
Is the Thermal Cutoff really needed?
Not if your fire insurance is paid up.

Even then. Since if the insurance inspector finds that the wall adapter
was tampered with, you better have a good lawyer.

It's only a $2 part. Sounds like 130 degC, 1 A.

If it goes again, the transformer is overheating either because there
are some shorted turns in the transformer or the load is too high.

Or, just get a new wall adapter.

NEVER defeat a safety device except possibly for brief testing.

Absolutely agreed. Do not bypass this essential protection device

Arfa


wrote:

Doh,Thanks for catching that everybody.
I don't know why it is,but I seem to always pass over the most simple
and obvious things when it comes to this stuff. I'm sure if I would
have stopped and thought about it and let everything marinate awhile I
would have figured out what a stupid idea/question that was.

Thanks again guys,its most Appreciated

One more thing, They tend to go open from the heat of soldering them!
The leads either have to be left pretty long and you have to be very
quick or you can use a heat shunt (e.g. a pair of foreceps with a little
pad of copper braid between the jaws latched onto the lead between where
you are soldering and the body of the part.

Metal cased ones have the case live. You cant swap a plastic cased
thermal fuse for a metal one safely in most mains voltage applications.
If you cant get the correct temperature one easily anything +- 5deg
should be fine but for liability reasons, if for a customer go under
rather than over.

Lastly and *NOT* related to your question, this is a worldwide *USENET*
group and is in no way owned by or even part of Google (They do have
their own groups as well that dont make it out here). The order we (non
google groups users) see posts on our screen is in no way related to
what Google shows you. Users of Google Groups frequently (a) dont quote
at least some of preceding messages, and (b)frequently seem to start a
new thread that the rest of us cant see is connected to the original
question. The end result is they tend to get ignored because it appears
that they aren't polite enough to thank the people that helped them. In
some cases this is true, though I suspect thats its often the case that
their reply simply got 'misfiled'. Fortunately this time your reply
*was* properly threaded. I've taken the liberty of PUTTING BACK
(quoting) the previous posters in this thread, although some might say I
should have trimmed their replies a bit more.

The Google Reply button at the bottom is NOTORIOUS for causing this
problem, though I understand that if you use the Reply on the options
dropdown on the right of the message header it does let you quote the
preceding message.

One replies at the bottom (or interleaved below each question or point
you are responding to because:

A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?

(I defend anyone's right to top post as freedom of expression, but I beg
you, please dont do it *here*)

Finally, the situation with spam from Google users + general abuse of
usenet is getting so bad that an increasing number of users on *many*
groups are advocating killfiling (permanently blocking) *all* messages
posted via Google. *Every* Goggle user who makes the effort to learn
and follow the customs of the USENET groups they are using improves
their chances of being listened to considerably. The users most likely
to block you are often the longest standing ones with the most
experience :-( You may wish to get a proper newsreader program and
subscribe to a USENet provider (usually called a News Server), to let
you break away from Google's restrictions and problems.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL:

Charles wrote:

Is the Thermal Cutoff really needed?

Not if your fire insurance is paid up.


Bad advice from 'Charles', as usual.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida