[GreenKeys] LTSpice

[Jeffrey D Angus]

On 7/19/2013 12:11 PM, John Nagle wrote:
> That's good to know.  I've been using 1uf and 100 ohms.  Same
> R/C ratio.  Note that you need at least 500V ceramics for that
> snubber; there's a big voltage spike when the selector magnets
> dump.
The same ratio perhaps, but way different results.

Similar to the 100 nF and 470 ohm combination, this has considerable
ringing. And the overshoot. Oh my.... It peaks at 276 volts. 156v (130% )
above the nominal 120 v supply.

This is why I ended up with 470 nF (0.47 uF) and 470 ohms.
I'm using yellow Mylar caps rated at 630 vdc.

With .47 uF and 470 ohms, I get a peak of 144 vdc. Only 24 v (20%) above
the nominal 120 v supply. And only one basic ring.

Jef-1.0
wa6fwi

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