ORIGINAL: kenhiraihnl
ORIGINAL: gnd2
ORIGINAL: kenhiraihnl
the switch is rated at 3 amps @ 125vac, which equals 30 amps @ 12vdc...
No, actually 3 amps @ 125VAC does NOT equal 30 amps @ 12 vdc. You're thinking of power dissipation, but switches don't dissipate power, they either transmit (switch closed) or block (switch open) it.
3 amps means the switch can handle 3 amps when the switch is closed. Period.
The 125VAC means it can BLOCK 125V without arcing when the switch is open.
The two values stand on their own, you can't trade off one for the other like you can with something like a resistor which dissipates power.
wow! thanks for the explanation...i guess with a 3 amp weak link in my power setup, i'm living on borrowed time...so far, however, it seems to work just fine...maybe i should look for a 30 amp switch? ken
I would definitely suggest at least a 25 amp switch.
You have a little leeway due to things like temperature (most consumer products are rated up to 70 deg C) and the fact that you're not actually pulling the max load all the time, but being off by nearly a factor of 10 I'd say you're pushing your luck pretty hard
btw, the package for the radioshack 275-624 toggle switch says, 'rated 3a at 125vac or 1a at 250vac'
I have to admit I don't know why they would say that. I hope it doesn't mean I'm completely off base but I think I'm right.