At 08:33 AM 8/3/01 -0400, you wrote:
>> if the load is
>> inductive (or capacitive) there will be a phase shift between the DC
>> voltage and DC current. However, the fact remains that a triac will turn
>> off when conducting the DC current of a half or full wave rectified
>signal.
>
>It's more than just a phase shift issue.  Series inductance can cause the
>current to never reach zero (or fall below the triac dropout current).

Well, it obviously *must* pass through zero twice per cycle. But the
problem with inductive loads is that excessive dv/dt during the time
period when the current is less than the holding current (passing
through zero), particularly for triacs, may prevent commutation
from reliably occuring.

Best regards,
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