Go Down

### Topic: AC Light Dimming (Read 26959 times)previous topic - next topic

#### Gromain59

#45
##### Nov 14, 2009, 09:40 am
Quote
What do i have to change to make the flicker go away?

50hz gives a zero cross detection every 10ms
So, 60hz gives a zero cross detection every 8ms

I think the last timer interruption (49) appears after a new zero cross.

You have to recalculate all the values retard[] (reduce the value)

but first, you can test by limiting the number of timer interruption by change value 49 in
Code: [Select]
`if (c2>=49){` to 45, or maybe less

Don't forget to feedback  your test.

Gromain
"pour résoudre un gros problème, il est souvent plus facile de le diviser en petits problèmes élémentaires..."

projet domotique xPLDuino
IRC: freenode #xplduino

#### Mike.Dausch

#46
##### Nov 19, 2009, 06:56 am
Thanks big time.
I changed the value to 41 and the flicker is nearly gone.

Here is the code I translated:

[code]

/*
DIMMERS 120V 60Hz (8-channel Possibly more)

by Gromain59
Translated By Mike Deuschle
mike.dausch@gmail.com

Material part:
- Triac driven by a digital output via an optocoupler
- AC opto-coupler for detecting the zero crossing of phase

Software part:
- A hardware interrupt input 2 at the zero crossing of phase
- A software interrupt that occurs between 100us and 1400us.
=> Interrupt interval is variable to obtain a light curve by linear orders, because of the shape of the sinusoidal signal.
we have:
1. Detection of the transition to zero on input 2
2. execution of detection_zero (): processing channel with a setpoint of 0% and 100%
3. deactivating hardware interrupt, enabling the software interrupt on the basis of delay

• 4. interrupt after delay [c2] ?s (c2 = 0)
5. execution of controle_canaux ()
=> Index increment c2
and if c2 is greater than 49, then this is the last cycle
=> Turn OFF of all channels
=> Activate the hardware interrupt
otherwise:
=> Activation of output channels with 98% to record (either a 469?s delay) or if
=> Interrupt reconfiguration of time with another delay, delay [c2]

To change the setpoint of a channel, you must send via the serial monitor a frame of the form:
" D/0/45/F"
=> Space
=> "D" to indicate the start of the frame
=> "/" As separator
=> The affected channel (0 to 7 here)
=> "/" As separator
=> The desired level (from 0% to 100%)
=> "/" As separator
=> "F" to indicate the end of the frame

Once the frame received, the function sscanf is responsible for retrieving data.
It converts the received record levels (0 to 50 levels)

Resources:
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1230333861/30 for first test
http://www.hoelscher-hi.de/hendrik/english/dimmer.htm for electronics
http://www.abcelectronique.com/bigonoff/domocan.php?par=3efd4 for electronics and soft (PIC)
arduino forum

*/

#include <TimerOne.h>  // for the interruption time http://www.arduino.cc/playground/Code/Timer1
#include <stdio.h>  // for the treatment of the frame containing the change orders

// timeout value for the reception of the frame
int tps_max_lecture = 200; // reading code, counter max between all the characters of a code
int tps_max_carte = 1000; // max meter between reception of a character

long curve[] = {
1469 , // 98 % 1 225,3V retard / zéro = 1469 ms
287 , // 96 % 2 222,7V retard / zéro = 1867 ms
234 , // 94 % 3 220,6V retard / zéro = 2154 ms
201 , // 92 % 4 218,2V retard / zéro = 2388 ms
180 , // 90 % 5 215,4V retard / zéro = 2589 ms
164 , // 88 % 6 213,3V retard / zéro = 2769 ms
152 , // 86 % 7 210,8V retard / zéro = 2933 ms
143 , // 84 % 8 208V retard / zéro = 3085 ms
135 , // 82 % 9 205,7V retard / zéro = 3228 ms
129 , // 80 % 10 202,8V retard / zéro = 3363 ms
124 , // 78 % 11 200,5V retard / zéro = 3492 ms
120 , // 76 % 12 197,6V retard / zéro = 3616 ms
116 , // 74 % 13 195,2V retard / zéro = 3736 ms
112 , // 72 % 14 192,4V retard / zéro = 3852 ms
110 , // 70 % 15 189,6V retard / zéro = 3964 ms
108 , // 68 % 16 186,8V retard / zéro = 4074 ms
106 , // 66 % 17 184V retard / zéro = 4182 ms
105 , // 64 % 18 180,9V retard / zéro = 4288 ms
103 , // 62 % 19 178,1V retard / zéro = 4393 ms
102 , // 60 % 20 175,1V retard / zéro = 4496 ms
101 , // 58 % 21 172,1V retard / zéro = 4598 ms
101 , // 56 % 22 168,9V retard / zéro = 4699 ms
100 , // 54 % 23 166,2V retard / zéro = 4800 ms
100 , // 52 % 24 162,6V retard / zéro = 4900 ms
100 , // 50 % 25 159,3V retard / zéro = 5000 ms
101 , // 48 % 26 155,8V retard / zéro = 5100 ms
100 , // 46 % 27 152,6V retard / zéro = 5201 ms
101 , // 44 % 28 149,1V retard / zéro = 5301 ms
102 , // 42 % 29 145,3V retard / zéro = 5402 ms
103 , // 40 % 30 141,8V retard / zéro = 5504 ms
105 , // 38 % 31 138V retard / zéro = 5607 ms
106 , // 36 % 32 133,8V retard / zéro = 5712 ms
108 , // 34 % 33 130V retard / zéro = 5818 ms
110 , // 32 % 34 126V retard / zéro = 5926 ms
112 , // 30 % 35 121,7V retard / zéro = 6036 ms
116 , // 28 % 36 117,1V retard / zéro = 6148 ms
120 , // 26 % 37 112,6V retard / zéro = 6264 ms
124 , // 24 % 38 107,7V retard / zéro = 6384 ms
129 , // 22 % 39 102,4V retard / zéro = 6508 ms
135 , // 20 % 40 97,2V retard / zéro = 6637 ms
143 , // 18 % 41 92V retard / zéro = 6772 ms
152 , // 16 % 42 85,7V retard / zéro = 6915 ms
164 , // 14 % 43 79,4V retard / zéro = 7067 ms
180 , // 12 % 44 72,8V retard / zéro = 7231 ms
201 , // 10 % 45 64,8V retard / zéro = 7411 ms
234 , // 8 % 46 56,4V retard / zéro = 7612 ms
286 , // 6 % 47 46V retard / zéro = 7846 ms
399 , // 4 % 48 32,4V retard / zéro = 8132 ms
500 , //
1469  // 2 % 49 0V retard / zéro = 8531 ms
};

int set[] = {    // set channel level (0 = 100%, 50 = 0%)
0, // Output 0
0, // output 1
0, // output 2
0, // output 3
0, // output 4
0, // output 5
0, // output 6
0, // output 7
};

int output [] = { // assign a pin for each channel.
4, // Output 0
3, // output 1
5, // output 2
0, // output 3
0, // output 4
0, // output 5
0, // output 6
0, // output 7
};

volatile int c1 = 0; // index c1 for reading data from each channel (No pin, luggage)
volatile int c2 = 0; // c2 index number passing through the loop control phase delay (49 passages)

// Definition of macros to drive the output
#define lightON(index) (digitalWrite(output[index], HIGH))
#define lightOFF(index) (digitalWrite(output[index], LOW))

void setup () {// Start of setup

// Initialize the serial
Serial.begin (9600);

// Initialize the channel outputs (triacs)
for (c1 = 0; c1 <= 7; c1++) {// we traverse the 8 channels to configure
pinMode(output[c1], OUTPUT); // we associate each channel has a pin, which sets the output digital
lightOFF(output[c1]); // and we switch off the output
}

Serial.println( "Gromain 8-CHANNEL DIMMER v0.2");
Serial.println( "FRAME EXPECTED: <space> 'D' / 'Output Port' / 'Value of DIM' / 'F'");

// Initialize the interruption time Timer1
Timer1.initialize(); // Initialize TimerOne library for the freq we need

// Attach the interrupt 0 to pin 2 for the detection of zero crossing (Zero Cross Detection)
attachInterrupt(0, detection_zero, FALLING); // Attach an Interrupt to Pin 2 (Interrupt 0) for Zero Cross Detection

} // End of setup

void detection_zero() {// function associated with the interrupt 0

detachInterrupt(0); // disables the interrupt on zero crossing

c2 = 0;

for (c1 = 0; c1 <= 7; c1++) {// we scan the 8 outputs to check their orders
if (set[c1] >= 49 ) {// if set 0%
lightOFF(c1); // then we switch off
}

if (set[c1]<= 0){// if set 100%
lightON(c1); // then we light
}

}

Timer1.attachInterrupt(controle_canaux, curve[c2]); // we attach the interruption time

} // End of detection_zero

void controle_canaux() {// here we verified whether the triac must be initiated

c2=c2++;

attachInterrupt(0, detection_zero, FALLING); // we attach an interrupt on pin 2 (interrupt 0)
Timer1.detachInterrupt(); // we detach the interruption time

if (c2 >= 41) {// If last cycle then (best at 41 for 60Hz)

for (c1 = 0; c1 <= 7; c1++) {// we scan the 8 outputs
lightOFF(c1);  // and we put out the channel for the next cycle
}

}
else { // else

Timer1.attachInterrupt(controle_canaux, curve[c2]); // we attach a break time

for (c1 = 0; c1 <= 7; c1++) { // we scan the 8 outputs to check their orders
if (set[c1] == c2) // if is set equal to the processed (no change in the loop)
{lightON(c1);} // then we light the channel
}

} // End function controle_canaux

}
void loop() {// Main Loop

int n = 0;

if (Serial.available ()> 0) {
n = lecture();
}

}

int lecture() {// read a frame type: "D / aaa / bbb / F
// Or "D" starting character frame
// Or "yyyy" No output which is set to modify
// Or "bbbb" new set of output (between 0 and 100%)

char buf[15] = "              ";
int timeout = 0;
int i = 0;
int n1 = 0;
int n2 = 0;
char c1, c2;

while (Serial.available() > 0) {
if(i!=14){
i++;
}

timeout++;

if (timeout>tps_max_lecture)
{Serial.println("T1");
return -1;
}
if (timeout> tps_max_lecture)
{Serial.println("T2");
return -2;
}
}
sscanf(buf, "%c/%d/%d/%c", &c1, &n1, &n2, &c2); // decoding frame

if (c1 == 'D' && c2 == 'F') {// Check if the plot starts out by D and ending in F

int nouv_cons = n2;  // we store the new value for the work then

nouv_cons = constrain(nouv_cons, 0, 100); // on the new terminal value between 0 and 100%

#### Mike.Dausch

#47
##### Nov 19, 2009, 06:59 am
... Continue (i ran out of characters)

Serial.print("Output ");
Serial.print(n1);
Serial.print(" , new value of: ");
Serial.print(nouv_cons);
Serial.print(" % index, delay: ");

set[n1] = (50 - (nouv_cons / 2)); // it converts the value 0-100% in no phase delay

Serial.println (set[n1]);
}
else // if character from the beginning or end of frame not recognized
{Serial.println("Code Unknown");}

return i;

}

#### cgriffin

#48
##### Nov 29, 2010, 05:43 pmLast Edit: Nov 29, 2010, 05:46 pm by cgriffin Reason: 1
Can a BTA20 be dropped in place of the BTA10 to provide more amperage.

I need to control several 2kw heating elements

#### Tesla

#49
##### Nov 29, 2010, 05:53 pm
You should be able to use a BTA20, as long as you make the proper adjustments to the circuit to safely carry the additional current.  Larger traces, wider trace spacing, etc.  As always, give yourself extra space around the components and traces, and once it's all working, I would suggest coating the solder side of your board with a protectant, such as silicone or epoxy.  This makes repair difficult to impossible, but also makes the thing much safer in the work environment.

--Tesla

#### cgriffin

#50
##### Nov 29, 2010, 06:07 pm
Very cool,  thank-you very much.

I will reply back with the results if I don't turn myself into a cinder.

#### Tesla

#51
##### Nov 29, 2010, 06:17 pm
Just keep your hands and feet clear of the system while it's energized, and be aware of stray bits of wire and such. Make sure whatever you have it set on is clean and non-conductive. I usually use a chunk of cardboard if I'm testing it outside a proper mount or enclosure.
Good luck with it!

--Tesla

#### cgriffin

#52
##### Jan 19, 2011, 09:54 pm
Still working on this,   out of curiosity what would be required to run on 220V AC?

Go Up