I need to have an LED floodlight parallel to a relay coil, I want to learn to design it correctly and I'm worried about the resistances. They have a 120VAC source. The specs for the relay coil are "Input voltage: 120VAC, Rated load current= 12Amps" and the specs for the light (http://www.ledlight.com/SearchResult.aspx?KeyWords=35644) are "Consumes 10W, powered by 100-240VAC." From my knowledge, the LED current is P/V=10W/120V≈83mA, thus the resistance of the light is 120/.083=1440 ohms. I have no idea if this is the right way to calculate the resistance of my light. Also from my knowledge, the coil is 120V/12A=10 ohms.
*If the lights specs are 100-240VAC, does that mean the voltage is a variable, or is it forced by my 120Vac power source? (Is voltage a changing variable? Which variables change or stay constant)?
*How exactly would I calculate the resistance of the light (on paper, w/out an ohmmeter)?
*If I am correct in my calculations, does that mean I need to add a 1430 ohm resistor in series with my relay coil to make the current flow evenly through the parallel wires?
*If the lights specs are 100-240VAC, does that mean the voltage is a variable, or is it forced by my 120Vac power source? (Is voltage a changing variable? Which variables change or stay constant)?
*How exactly would I calculate the resistance of the light (on paper, w/out an ohmmeter)?
*If I am correct in my calculations, does that mean I need to add a 1430 ohm resistor in series with my relay coil to make the current flow evenly through the parallel wires?