need help with MOC3022 and BT137

[aruna1]

hello I'm making a remote dimmer and I'm having some trouble with the dimmer circuit. (opto isolator used is MOC3022 and triac used is BT137)

i use following circuit as the dimmer.but after supplying power bulb begins to flicker
**broken link removed**

but if i bypass opto-isolator triac turns on continuously
**broken link removed**
. can some one point me what is the error?

i have attached a video too

 

[aruna1]

What is the "frequency" of the flicker? It might be the 50Hz you're seeing.

i'm not sure about frequency how ever in second circuit there is no flicker

 

[BrownOut]

I deleated my response after viewing your movie. This doesn't look like a workable control circuit. The control has to be synchronized with the cycles of the mains in order for a triac to work. Otherwise, you can only control "on" and "off" I don't know why your light flickers as it does. I'm not familiar with your opto, but I suspect there are others on here who has knowledge of it.

 

[aruna1]

I deleated my response after viewing your movie. This doesn't look like a workable control circuit. The control has to be synchronized with the cycles of the mains in order for a triac to work. Otherwise, you can only control "on" and "off" I don't know why your light flickers as it does. I'm not familiar with your opto, but I suspect there are others on here who has knowledge of it.

but this is the circuit given in moc3020-3023 data sheet (only difference is in data sheet circuit has 240v 60hz)

 

[blueroomelectronics]

As mentioned it must be triggered on the zero crossing to work as a dimmer.

 

[aruna1]

As mentioned it must be triggered on the zero crossing to work as a dimmer.

so how to do that? what are the changes i have to do?

 

[aruna1]

sorry sir but i dont understand .i'm a novice to these stuff

 

[marcbarker]

edit: I just realise after I posted and deleted it. The MOC is a traic output.

Is U1 LED is connected wrong and leakage current is slightly turning it on?

 

[aruna1]

Isn't the maximum voltage of U1 exceeded when the lamp is fully dimmed?

Maybe the output is connected backwards and it's breaking down?

well moc3020 can hold till 400v

 

[aruna1]

output is connected correct way

 

[marcbarker]

output is connected correct way

Is the LED conencted right way round? ( I have to ask)

I can't see anything wrong with your 'trial' circuit, despite what others say about needing zero-crossing control.

If you're going dim though, maybe you do need some voltage detector circuit.