zero crossing triac switch

[vicky.pace]

Dear all,

Please tell me hw I can switch a triac at zero cross state. I found a opto(MOC3162) in which this provision is inbuit but device is not available in India.

If someone can suggest a small simple circuit for the same. It wound be a great help to me.

thanks.

Vicky

 

[pranam77]

Dear all, Please tell me hw I can switch a triac at zero cross state. I found a opto(MOC3162) in which this provision is inbuit but device is not available in India. If someone can suggest a small simple circuit for the same. It wound be a great help to me. thanks. Vicky

For triggering at Zero crossings, you need to construct a Zero cross detector circuit and get a ZC signal, and proportionally trigger the triac at the required time.
In India, you'll get almost every component required for an average electronic Industry. Only thing is, you'll have to search for a better source of getting it. Anyways..You may use MOC3041 or MOC3061 which you'll find with most of the componenet vendors.
You may also refer this link given below for a thread related with ZC.

Cheers

 

[FvM]

In India, you'll get almost every component required for an average electronic Industry.

That's also my impression, but I didn't want to give clever comments from a distance. MOC302x have no ZCD circuit, but MOC304x and MOC306x have, there are also more replacement types with different names. You have to check the voltage rating and the required trigger current.

Of course you can design a discrete ZCD circuit, but I fear, it would be most likely neither small nor simple on first attempt. These standard opto tríacs are used since decades, there is no better solution for a wide range of applications.

 

[pranam77]

MOC302x have no ZCD circuit, but MOC304x and MOC306x have

Thanks Frank for pointing out the mistake. Actually i intended to write it as 3061. But having some calculations in mind, i wrote 3021. Anyways it is corrected now. Cheers