This is very basic for those who deal with electronics. But I am very rusty with the relationship here. I have a product that holds items that need to be heated. The current method for heating is a 3watt 120VAC light bulb. We are designing an improved version and we are thinking of other methods for heating. There are some heat tapes that might fit the bill as there are power resistors. If I did decide a resistor is what I want to use, how do I go about sizing it? Again this is an item that must use standard 120VAC house power and output about the same heat of a 3 watt 120VAC bulb. Am I looking for a 3 watt resistor with XXXohms. What would the equation for the relationship be?
Also, there small heat pads for spot heating I have found. The web sites assume more of the viewer than is helpful. Are there any of these items that could work with 120VAC and not use a transformer. I have never used the heat tapes that are intended to prevent pipes from freezing. I know they use 120VAC but not sure if they have a transformer build in.
The area to be heated is only about 4 square inches. The item is unit is located in heated areas ~ 70F. The items to be heated are heated to about 100F.
I hope I have provided sufficient info.
