Hi again,
Here are the changes that will help the problems.
1. Short out the fuse where it is now, move it to be in series with the N input line terminal. Make it a 500ma unit if you can but no larger than 1 amp.
2. Change R560 to 330 ohms, at least 2 watts for now. We can probably get away with a 1 watt here.
3. Remove C2, the 394k cap.
4. Make sure the bridge rectifier is rated for at least 1 amp.
5. Disconnect everything from the bridge rect (+) output, except the C5 cap (+) terminal.
6. Keep C5 capacitor (+) terminal connected to bridge rect (+) output, but that's the only thing to connect the the bridge (+) output.
7. Connect a 100 ohm resistor between the capacitor C5 (+) terminal and the zener cathode.
8. Connect the rest of the circuit to the zener cathode (like the 555 etc.).
9. Redraw the circuit and post here.
10. Test.
The above changes will help it work better and also make it safer.
Hi again, after couple of months... I've decided to continue the thread as people are asking me in private messages how the things are going with this.
First of all, apologies to MrAl for the delay... I'll not go into details why, but I'll just mention I didn't stop working on this project when I had some free time.
I still have problems.
Second, I did tested the suggestions from MrAl, also did other tests, as a result - no sufficient power for my circuit and still too much heat generated from the current limiting resistor (and the one which protects the zenner).
The general issues are 2: heat produced (especially when bulb off) and not enough current to power the whole circuit - when the bulb is ON.
So therefore I've spent a lot of time reading arround and found out MrAl is right (actually I knew it before, but I wanted to understand better).
Now I am sure I need to go with the approach to detect the zero crossing and to delay the moment the triac is fired. Hopefully this delay right after the zero crossing would give me some power to feed my curcuit, without dimming the bulb (exactly as MrAl was pointing several times already before). The idea is to have as much as brightness as possible.
So I am now close to put on my breadboard the following:
/Important for new readers here: The whole thing should work without Neutral line! I have only the Live wire and the other one is the wire connected to the bulb, so the whole circuit will be in series with the bulb all the time!/
- H11AA1 will be used (not sure if it will operate properly as the bulb is connected in series) to detect the zero crossing (with 22k resistors infront, 1W at least) and it will trigger a CMOS 555 in monostable mode;
- The 555 will produce a time delay (not sure how much time... maybe 2 ms or so);
- After the delay the 555 pin 3 will go low and thus MOC3052 (random one) will fire the TRAIC gate;
- The Triac will turn off at the end of the sine wave; As it will be again zero crossing, the 555 will not let the MOC driver to turn on the triac until the next delay cycle finish.
Furthermore, I've managed to utilize my own RF receiver on 315Mhz (with the respective decoder IC), and got rid of the relay as MrAl was advising me before. That should save some power. So no relay anymore in this circuit! The output signal from the receiver drives a flip-flop CD4013, which is also driven by the manual button switch (debounced with schmitt trigger accordingly). The issue now is that threre is not enough power for the receiver when the bulb is ON. If I power this part of the circuit with battery, everything works as I want...(I don't want battery in this project).
I am going post diagram and results soon when time to do it.
Again apologies for the delayed posts but I am doing all this as a hobby only in the available time.
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