Dimming 500W work light

I am fairly new to electrical systems, so I could use some help finding the right parts for a project I am working on. I would like to control the brightness of a very powerful light using output from a proximity sensor with an Arduino. I have successfully made a prototype (schematic attached as jpg) using a small halogen light (50W, 130V halogen flood light) and this AC dimmer module (3.3V/5V logic, AC 50/60hz, 220V/110V; power: 600V - 16A).

So, my next step is to move from this relatively weak halogen bulb to a powerful one. Let’s say that I am trying to use this 500W work light. That light’s spec sheet says that the light “operates on 120V AC.”

Can I use the dimmer I have with this new 500W, 120V light (replacing the 50W, 130V light) or will it not be able to handle the power requirement? I am trying to figure out if I need to purchase additional parts.

Hopefully I’ve provided enough information, and thanks in advance for the help!

PS: Here is the code I’ve been using for the smaller light just in case that is helpful to see.

//The following sketch is meant to define by function the smooth changes of dimming values in a range of values defined by user 
//values are defined in range from 0 to 100%

#include <RBDdimmer.h>
#include <Wire.h>
#include <LIDARLite.h>

#define USE_SERIAL  Serial
#define outputPin  10 
#define zerocross  2 // for boards with CHANGEBLE input pins

//dimmerLamp dimmer(outputPin, zerocross); //initialase port for dimmer for ESP8266, ESP32, Arduino due boards
dimmerLamp dimmer(outputPin); //initialase port for dimmer for MEGA, Leonardo, UNO, Arduino M0, Arduino Zero

LIDARLite myLidarLite;

const float close_thresh = 50;
const float far_thresh = 500;
const float m = -100 / (far_thresh - close_thresh);

void setup() {
  USE_SERIAL.begin(9600);

  pinMode(bLED, OUTPUT);
  pinMode(gLED, OUTPUT);
  pinMode(rLED, OUTPUT);  

  myLidarLite.begin(0, true); // Set configuration to default and I2C to 400 kHz
  myLidarLite.configure(0); // Change this number to try out alternate configurations
  
  pinMode(outputPin, OUTPUT);
  pinMode(zerocross, INPUT);
  dimmer.begin(NORMAL_MODE, ON); //dimmer initialisation: name.begin(MODE, STATE) 
  dimmer.toggleSettings(0, 100); //Name.toggleSettings(MIN, MAX);
  dimmer.setPower(100);
  dimmer.setState(ON); // state: dimmer1.setState(ON/OFF);
}

void loop() {
  int dist = myLidarLite.distance();
  dist = dist-10;
  if(dist<0){
    dist=0;
  }
  
  int brightness = m*(dist-close_thresh)+100; //linear dropoff
  
  if(dist<close_thresh){
    dimmer.setState(ON);
    dimmer.setPower(99);
  }
  else if(dist>far_thresh){
    dimmer.setState(OFF);
  }
  else{
    dimmer.setState(ON);
    dimmer.setPower(brightness);
  }

  USE_SERIAL.print("dist = ");
  USE_SERIAL.print(dist);
  USE_SERIAL.print("        dimmer power = ");
  USE_SERIAL.println(dimmer.getPower());
}

It should work fine. Power (watts) is calculated as Voltage x Current so 500W at 120VAC is a little more than 4 Amps.

There is a turn-on current surge with incandescent lamps (including halogens) but it should be OK.

LEDs produce a lot more light... all floodlights I've seen for sale (or even in use) the past few years are LED, it comes a bit as a surprise to me to hear halogen is still in use!

LEDs produce a lot more light...

No... More light per-watt. :wink:

I have lots of LEDs and a few LED "light bulbs" and none of them put as much light as a 500W halogen. And, 'good luck' finding a dimmable LED worklight (or equivalent). You could build one but it would be a lot more expensive and a lot more work.

Thanks for the quick responses! I'll get that work light and connect it to the dimmer soon. It's good to know that I won't blow up or break anything :stuck_out_tongue_closed_eyes:

Design your own load driver with a more powerful Mosfet (with a heatsink) if you like.

hesam_m:
Design your own load driver with a more powerful Mosfet (with a heatsink) if you like.

Did you miss the AC part perhaps?
Not a good idea to use a MOSFET for that.

wvmarle:
Did you miss the AC part perhaps?
Not a good idea to use a MOSFET for that.

Generally Yes, but there are some tricks to do so

I guess there are, but I really don't see any reason not to go for the standard and simple phase cutting by TRIAC here.

wvmarle:
I guess there are, but I really don't see any reason not to go for the standard and simple phase cutting by TRIAC here.

I agree with you, no problem. I just described another option. for sure your method is better