I'd like to make an LED nightlight for my twins that runs along the top of their wall and shines light up onto their ceiling (sortof like
) I've read Bill's tutorial on LEDs and think that I have a basic understanding of the project but am concerned about safety and also am not sure how to figure out what the heat output will be for the LED. I don't want a fire risk!
My preliminary plan is to wire 24 blue LED (datasheet) in 6 parallel strands of one current limiting resistor (100 Ohm) + LED in series. Each LED has a Vf of 3.4v @ 20 mA. I used the LED.Lineara1.Org to design the LED array.
I plan on buying a 12VDC voltage regulator to plug into the wall like this one rated at 1000mA.
I thought that I would mount each LED in wooden molding (maybe like this) into which I had drilled an appropriately sized hole. I would mount the LED so that 80% of the bulb was exposed to the air. The wire, resistor, and soldered connections would be stapled to the back of the molding so that it was sandwiched between the molding and the wall (or ceiling).
I could use some help with a few questions. First, would something like this work? Second, would it be safe i.e. Am an idiot for thinking of putting something homemade in my childrens' room? (I am anticipating a future conversation with my wife). Third, how do I calculate the appropriate gauge wire to handle the current (the wizard calculates it at 160 mA for the total array). I guess a related question is whether 160mA at 12V is dangerous if one of my children decided to pull out an LED or something similar.
We've built simple robots together using our arduino and breadboard but nothing that would permanently plug into the wall. I really like the idea of building this with them to model a DIY spirit but don't want to burn the house down either.
Any guidance would be appreciated.
Dan
My preliminary plan is to wire 24 blue LED (datasheet) in 6 parallel strands of one current limiting resistor (100 Ohm) + LED in series. Each LED has a Vf of 3.4v @ 20 mA. I used the LED.Lineara1.Org to design the LED array.
I plan on buying a 12VDC voltage regulator to plug into the wall like this one rated at 1000mA.
I thought that I would mount each LED in wooden molding (maybe like this) into which I had drilled an appropriately sized hole. I would mount the LED so that 80% of the bulb was exposed to the air. The wire, resistor, and soldered connections would be stapled to the back of the molding so that it was sandwiched between the molding and the wall (or ceiling).
I could use some help with a few questions. First, would something like this work? Second, would it be safe i.e. Am an idiot for thinking of putting something homemade in my childrens' room? (I am anticipating a future conversation with my wife). Third, how do I calculate the appropriate gauge wire to handle the current (the wizard calculates it at 160 mA for the total array). I guess a related question is whether 160mA at 12V is dangerous if one of my children decided to pull out an LED or something similar.
We've built simple robots together using our arduino and breadboard but nothing that would permanently plug into the wall. I really like the idea of building this with them to model a DIY spirit but don't want to burn the house down either.
Any guidance would be appreciated.
Dan
Last edited: