At 05:16 PM 3/1/01 -0500, you wrote:
>
>=> Snubber network consists of a series 22 ohm, 0.25 W resistor with a 0.1
>uF 250 V capacitor. This will near-optimally damp EMI and and limit
>back-emf to 176 volts.
>
>Any comments as to the adequacy of this analysis or set of design rules?

Neither the triac rating or the ratings of either of the snubber
parts is adequate to meet minimum standards of safety and reliability.

Suggest you read up on expected line transients and fusing/heat sinking
requirements. Also, you might want to calculate the peak power in your
resistor and compare that to the data sheet rating. Also consider the
failure mode of carbon-film resistors.

Best regards,


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