>switches has a rating printed on it of..."35A at 6v or 20a at 12v". I check
<another..."20a at 6v or 10a at 12v". Dazed and confused I check a
>third..."35a at 6v or 12v".
Nick,
I suspect that this has something to do the the power handling
capability of the switch. Back in the days that I did substation work
I learned that the volt-amps remained basically constant across a
transformer so as you reduced the voltage the amperage went up (I know
that we are talking DC here not AC). We rated transformers in va -
volt-amps. This would explain the switches that have 2 different
ratings, particularly the second one as the volt-amps are constant at
1200va.
The switch that has a single rating I can't explain. One possibility
is that the higher the voltage the better able a spark was to jump the
gap when opening or closing a switch. This arcing is distructive to
switches as, like with points in a distributor, it tends to weld the
contacts together. We had special devices mounted on the switches to
minimize the damage from arcing by breaking the contact very quickly
and not giving the arc time to form, Maybe this switch has something
similar.
Regards,
Bruce Brandt
bbrandt@tcmail.frco.com
Austin, TX
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