Wednesday, Feb 03, 2010 at 11:34
They have a sealed bi-metallic type switch bonded to the Aluminium food container and it cannot be modified unfortunately.
I think that inside the sealing is a sort of metal clad wirewound resistor which dissapates the heat.
Actually the 150c is enough as its all inside a plastic box.
My guess would be that the ones that claim 120c have skimped on the internal insulating layer.
By using two halfs and improving the insulating from the spare bits mine really works well with the heat coming from both the top and bottom.
This effectively reduces the heat leakage and makes it heat up faster and the temp cutout still operates, reducing power use.
Some of these things can be gimmicks but after 2 years of steady use it has proved to be quite an asset and the wife is the first to miss it, espically since
she discovered we can heat up heatbags in it.
While I was in there I added an indicator light , as well.
I actually worked out a temp sensor hooked up to a Pic based LCD readout , but that was overkill.
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