help for triac drivers

[deepakchikane]

Dear all..

do i know how to drive the moc..

i am attaching ckt here...

bt something is burning from ac side..

- - - Updated - - -

Dear all..

do i know how to drive the moc..

i am attaching ckt here...

bt something is burning from ac side..

this is application note of fairchild... can anyone help me out to chose the o/p resistors..??
looking forward to hearing you sooon

 

[betwixt]

Figure 8 and Figure 9 are correct in the data sheet and the values are correct. If something is burning you have it wired wrongly or the triac is faulty. The most common problem I have come across is the triac main terminals being reversed.

What are you driving the MOC with? Please show how you have it connected at the moment.

Brian.

 

[deepakchikane]

brian,
if main terminal gets reversed, will it cause a problem..

 

[betwixt]

If it is reversed the chances are the resistors around the MOC will be damaged and the triac will conduct all the time. The MOC itself would probably survive because the triac would by-pass most of the current around it.

Brian.

 

[deepakchikane]

brian...

absolutely u are ryt...

i observed same prbm....

thxxxx