"Gareth Magennis" wrote in
:


"Phil Allison" wrote in message
...

"Tony Hwang"

I understand they work on bi-metal strips.


** Nope - that is a temperature switch.

Thermal fuses like this one use the melting point of some material
and rely on a spring to open the circuit.

http://media.digikey.com/photos/Cant...1%20DF100S.jpg



.... Phil



This is the type Peavey have hidden in the mains transformer of the
Classic 30.
I only discovered it by accident when I decided to dissect an "open
circuit" one, no mention in the schematics AFAIK.

The owner had had 2 mains transformers replaced previously, seems,
from Googling, these transformers are woefully underpowered and often
break. Wonder if the only failing part is actually this switch?


Gareth.


see if you can get to the thermal fuse and replace it with something rated
better,or just bypass it for test,using an external fuse.

ISTR reading in SER about others who eliminated the thermal fuse and
successfully reused transformers.


Also,consider how instrument amps are often used.(misused?)



--
Jim Yanik
jyanik
at
localnet
dot com