[GreenKeys] Solid State relays

[Jim Haynes]

On Wed, 25 Aug 2010, Paul Kasley wrote:

>  use MOSFETs instead of SCRs. I'm not sure if you can
> find an optocoupler with a 300V VCEO transistor output that can pound 60mA
> directly. Also, you need to snub the coils to manage the inductive kick when
> the transistor turns off - a simple 1N4004/5/6 diode may do the trick
> without excessively lengthening the current pulses thru the coils.
>
Look at the Fairchild HSR312 and related products.  I haven't got around
to trying this yet, but it looked good - until someone pointed out that
the turnoff time is in milliseconds.