Controlling an 800w redhead light.

Projects General Guidance
1

Doing a project for my masters at the moment where i'm needing to control the brightness of a powerful light with an arduino dependent on the viewer moving closer towards a proximity sensor.

Alongside this the same sensor will also be controlling a constant tone going up in frequency as the viewer mover closer.

If anyone has any advice on how to accomplish the lighting aspect of this (or wether it's even possible), would be much appreciated.

Cheers :slight_smile:

edit: running the arduino through max-msp also if this makes a difference.

2

What kind of light? What operating voltage?

3

You can find constant current drivers that will accept PWM and/or analog levels for brightness control.
This company in particular http://www.meanwellusa.com/

4

I'm curious what a redhead light is, and how that differs from a blonde light.

5

promity sensing is dooable.

you can add sensor to detect distance.

With distance, you can set a value
then use that to do other things.

For that much power you need to get some sort of driver to control brightness of the light.

if that driver can accept a signal to dim, then you can make this all work.

The sound part should be the easiest part.

it all starts with what distance you are trying to read and how many directions you need to monitor

.

6

I'm curious what a redhead light is, and how that differs from a blonde light.

Different wattages of lights (in stage and studio lighting) are given different names. The big main spotlight is the "supertrooper".

Which explains the Abba song of the same name.

Mark

7

PaulS:
I'm curious what a redhead light is.

I think it's what the Heat Miser used at 40 seconds into this.

8

PaulS:
I'm curious what a redhead light is, and how that differs from a blonde light.

A redhead light is a general purpose floodlight -- around 800W like the poster describes. Blonde lights are much dimmer. rimshot

If OP wants to keep it simple he'd look at the ZeroCross Tail. There's an example Arduino sketch listed on that page, but if you have no familiarity with triacs and or what zero crossing refers to you'll want to read this tutorial on Dimmer Theory.

9

Blonde lights are much dimmer. rimshot

I knew someone was going to say that.

10

PaulS:
I'm curious what a redhead light is, and how that differs from a blonde light.

Redhead light is much superior to blonde light, of course.

:slight_smile:

11

cardboardD:
Doing a project for my masters at the moment where i'm needing to control the brightness of a powerful light with an arduino dependent on the viewer moving closer towards a proximity sensor.

Alongside this the same sensor will also be controlling a constant tone going up in frequency as the viewer mover closer.

If anyone has any advice on how to accomplish the lighting aspect of this (or wether it's even possible), would be much appreciated.

Cheers :slight_smile:

edit: running the arduino through max-msp also if this makes a difference.

You could try using a solid state relay something like this:

And then use the Arduino PWM to control it. You would need to get one, though, that has a fast response time (i.e. fast enough to follow the Arduino PWM frequency).

SOME of them seem to have some sort of internal low pass filter or capacitor and will not switch at more than 1 or 2 hertz. Of course, you need one that will switch at a few hundred hertz (at least the Arduino PWM rate).

Hope this helps.

12

Yeay, that does not work... All those solid state relays are based on a triac. And you can't simply PWM a triac. And more over, a lot of those have a zero cross detection build in so are useless to make a dimmer.