Hello All,
I'm working on an electronic thermostat and I am looking for an heatsink. I need something near 2W/oC I think the size should be between 2cm x 12cm x 7 cm ( 0.7in x 5in x 3in ).
I cannot find any or they are very expensive. Since almost every household electronic thermostat use one of this kind, it is available. I looked at newark, digikey, mouser... And I did not find anything, or what I can find needs a fan to force the air through the heatsink ( I cannot afford this ).
Moreover, I have a little general question about household electronic thermostat :
In my case, I will have both L + N line, so I have the easy one. But in Canada, there is only 1 wire to control the heater ( L or N since it is on 240 which is 2 live line wich are 180o different phase). When the heater is closed, the thermostat have full power since there is no voltage drop in the heater, but when the triac or the relay is closed (the heater is working) where the thermostat take it's power ? Does it need a battery? A super cap is used? Other way? The power of the heater is lowered to give some power to the circuits (ie. 1 cycle on 5 is to power the thermostat)?
Anybody has idea ?
Thank you!