At 10:38 04/09/97 -0500, you wrote:
>Consider using an Opto Isolator.  You could put series resistors on both
>sides of the LED, and then the Sensor side goes to your logic isolating
>the logic from the mains.  Also putting a zener and diode circuit in
>parallel with your LED could bring the "on" time closer to the zero line
>without frying the LED.
>
>Fred Thompson
>fthompso@mail.win.org

Only drawback, 240V @ 10mA = 2.4W dissipated in the resistors (assuming the
opto-isolator requires 10mA).

I suggested (by e-mail) using a small capacitor to couple an opto-isolator
to the mains. (along with a diode or three to protect the opto). This
dissipates hardly any power.

Keith.

------------------------------------------------------------
Keith Dowsett         "Variables won't; constants aren't."

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