Hi gang,
Was just introduced to this platform moments ago. I build industrial/steam punk illuminated art. I have an art-deco vintage toaster that I'm going to put some vintage bulbs in. No big deal here.
However, I thought it would be cool that when you turn the light on, it would pulse very slowly. I know how to wire, but am pretty cold on electronics. Is this platform even a reasonable option? If so, I'll dig in more.
Scenario: Turn on (110V USA) lamp, bulbs go from 0 to 10 (off to max brightness) over say 5 seconds. Then after x seconds the lamps slowly fade back to level 5 and so on.
LEDs are much easier to control with an Arduino (on/off, fade, blink) than incandescent bulbs, take less current and create much less heat. I would suggest looking into LEDs for your toaster. The pulsing fade would be pretty easy to do with an Arduino and LEDs,
I build industrial/steam punk illuminated art. I have an art-deco vintage toaster that I'm going to put some vintage bulbs in. No big deal here.
If you're going to see the bulbs, of course you'll want to use regular incandescent bulbs for a vintage look. But, if they are for illumination LEDs are easier to dim.
You can drive & dim a regular little LED (with a current limiting resistor) directly with the Arduino using PWM. And with a fairly simple driver circuit you PWM-dim 12V LED strips.
High power LEDs (1 Watt or more) are generally driven with a [u]constant-current* power supply[/u]. These come in dimmable & non-dimmable versions. The dimmable ones are generally controlled by 0-10VDC or by 10V PWM and you'll need a "little" (low current) driver to step-up the Arduino's 5V output.
Incandescent AC bulbs use [u]phase control[/u]. That means you need an additional circuit to read the phase and find the zero-crossing. Both the zero-crossing circuit and the AC ouput must be electrically isolated (usually optically isolated) from the low voltage circuitry (and isolated from you and other humans ). You can find examples of phase-controlled AC dimmers, but it gets a little complicated.
Technically, a dimmable LED power supply is controlled current, since the current is adjusted to control the brightness. But, it's different from a normal-everyday power supply which is constant/controlled voltage.
But there is another option. Yes, dimming mains bulbs is a bit harder. But if you use low voltage bulbs (like 12V or 24V) you can dim them with PWM just like a led. Yes, they take more current then a led so you need a beefier mosfet but it's not as hard as dimming a mains bulb.
Thanks for all the answers gang!
Toaster will not actually work anymore. I'm going to put the lamps behind the spring coils for "the look".
I know there are LED vintage bulbs, but couldn't find really small ones that I needed (<3.5" high), so incandescent.
I'll look at the referenced articles, but I'm wondering if there's a simpler "Radio Shack" answer to this?
How much do you guys think this project would cost? Sorry to ask so much before I really know the platform and what it does, but can't invest a lot of time or $$ then find out there's a much simpler solution I'm just not aware of.
I you can't spare money nor time I would drop the idea. Mains voltage can be lethal in multiple ways if not handled properly. So making a mains dimmer can be done by a hobbyist but can't be safely whipped together in an afternoon by a electrical noob...
). You can find examples of phase-controlled AC dimmers, but it gets a little complicated.