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1

Hello,
I have a little question, in K8064 T2 is it use for zero crossing need for triac dimmer?
But T1 what does it do?

2

One circuit is for voltage zero-cross, other circuit is for current zero-cross, as required for inductive loads.

3

Thanks very much.

4

Hello, I have a question to on related topic.

If you change the ZD1 of the T1 circuit to a 13V type what impact will this have on the functionality of the application. kind regards,