----- From: "Scott Fraser" <kn6f@D
-snip-
> >how is such a line (especially the white wire) supposed to be marked?

The National Electrical Code  says that the White conductor of a switch-leg
should never be switched, this means the white wire is the HOT side and the
black is the switched-hot, leaving the bare for safety ground.

> That is the case in many switched lighting outlets.
> Hot and neutral in the ceiling box, hot going to the switch box and switch
> leg returning to the lamp.

The trick is simple enough, the triac will have either full voltage across
it when the circuit is off, or a small voltage across it when on, stack in a
little more voltage drop in the on-state and you can have 5v to your circuit
and the remainder to the load (say 115 - 120v) think of a string of 6a
diodes with one 6a diode reverse parallel as a very large zener.

KF4HAZ - Lonnie

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