what is this little gizmo

[SparkyTris]

Can anyone cast any light on what this little silver widget is?
pretty sure the things that look like resistors are.... resistors.
but the thing in between the resistors....?

Untitled

• SparkyTris
• 15 Feb 2015
• 1

This was removed from a malfunctioning electric storage heater. it was installed in close physical contact with the end of a capillary tube which appears to provide thermostatic control to the metal output vane at the top of the heater.
it was electrically connected to the economy 7 supply 240VAC of the heater.

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[AndyPRK]

Crimp

Accelerator resistor

 

[333rocky333]

Could be a thermal fuse

Mind you just looks like an uninsulated through crimp, maybe a bodged attempt where the thermal fuse was took out
http://www.amazon.co.uk/Series-Meta...d=1424040136&sr=8-1&keywords=thermal+fuse+192

 

[bernardgreen]

Crimp
Accelerator resistor

I agree, and suggest the over size crimp is probably intended to act as a heat sink to get the heat out of the resistors using the leads of the resistors as heat conductors.

 

[SparkyTris]

please explain an "accelerator resistor"?

 

[333rocky333]

I dont recall them called that, but i think they mean similar to in a roomstat.
Im sure there used to make a clean break with the contacts rather than them sort of hovering between open and closed.
Hence the need for a neutral at the old style roomstats
Yo can see one on erics drawing wired between the N/O contact and neutral

Taken from this page

 

[bernardgreen]

A mechanical ( bi-metal ) thermostat switches ON at one temperature but switches OFF at a higher temperature. ( called hysteresis ) The difference can be several degrees and would result in noticeable temperature changes in the room. The "accelerator" compensates by adding a bit of warmth inside the thermostat when the heating is switched ON This means the bi-metal switches OFF at a room air temperature that is closer to the temperature at which the thermostat switched ON.

Electronic thermostats have a hysteresis of less than a degree so do not need the "accelerator"