AVR-Chat

I believe Sander is right. I'd keep the same current rating for lower 
DC voltages as for 28 volts.

Part of the reason the AC and lower voltage DC ratings are different 
is because of the arcing potential when you turn the switch off. 

Zack

--- In AVR-Chat@yahoogroups.com, Sander Pool <sander@...> wrote:
>
> 
> Hi Steve,
> 
> I'm no expert but looking at Ohms law I think it's safe to say that 
the 
> current rating is voltage independent. After all the resistance of 
the 
> switch is more or less constant as is the power dissipation 
capacity.
> 
> Voltage rating deals with how much voltage can be applied to an 
open 
> switch while still maintaining 'open' status and not sparking. This 
> depends on the distance between the contacts. It probably is also 
> related to how resistant the contacts are to arcing when contact is 
> made. If you put 1000V on a 120V switch you may blow away quite a 
bit of 
> contact material each time you close the switch.
> 
>     Sander
> 
> Steven Hodge wrote:
> >
> > I know this isn't anything about uC's but I have a general 
question
> > regarding toggle switch ratings, and there seem to be a lot of 
very
> > knowledgeable people on this list. Typically a data sheet rates a 
switch
> > for, say, 125 VAC, 250 VAC and 28 VDC. My applications, however, 
are
> > typically 12 VDC. Can I convert the 28 VDC rating to 12 VDC using 
a same
> > power equivalent, ie, if the 28 VDC rating is 4 A, then is it ok 
to 
> > run the
> > switch up to 28/12 x 4 = about 8 or 9 A? Thanks, Steve
> >
> >
>