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Volts and amps electrical switch question...

Thorsteenster

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Sorry to question something seemingly basic, but I've been trying to find the answer but not turning up much definitive.
I'm using two switches in my laser, one a trigger switch rated at AC 125V 2A:
And the other an arming switch rated at DC 50V 0.5A:
If the V going through these switches is much lower than its rating, such as a single 18650, is there an increase in current capability?

While a yes or no answer would be moderately appreciated, any further information and/or links would be greatly appreciated!
Thanks!

PS. Those are the smallest quantities I could find which are way more than I'll ever use. If anyone is interested in some of either, hit me up!
 
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RedCowboy

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Not so much no, it's not like there able to take X watts in any voltage and current arrangement, the contacts current rating is what matters in your case. So get a switch able to carry your current or use a relay or mosfet. If your laser draws 5 amps just get a decent pair of switches or else you will have annoying issues as the contacts get pitted.

That said if you are drawing 5A @ 7V and your switch is rated 10A @ 250V that's no problem, but a 2A switch even if it's rated at 500V will not have beefy enough contacts.

I like to get a switch with a higher Amp rating than I need, especially if it's Chineseium.
 

Thorsteenster

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Okay, I wasn't sure based on some research I'd been doing a while back on 12v and 24v battery systems but was more capacity related.
Either way the switches should be adequate for their intended use. The driver is set to 400ma, so I'd venture to say the battery won't see a load higher than that so should be fine for the 0.5A arming switch positioned between battery & driver. And if not, I've got 30 of em!

I would have liked to have used higher rated switches but space constraints dictated selections which also dictated a limit on LD power. I'll see how it goes with the 0.5A switches, hopefully well enough, otherwise it's back to the drawing board I reckon.
I did come across something with a capacitor I believe it was, on the switch to lower the current while the contacts make or break.

May have to delve into relays more and finding one small enough with a adequate rating.
 
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whysoserious11311

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May have to delve into relays more and finding one small enough with a adequate rating

If you are willing to go down the route of using SMD's something like a battery operated latching power switch would work. Sorry cant post links yet but if you search what is italicized; mosaic-industries has a nice schematic and description. You would need to fine tune some values but with a little modification it could substitute both your standby and switch.
 

RedCowboy

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I use these to switch 100v arrays @ 4.5-5A no problem.


Here's one rated at 16A / 12v > https://www.sparkfun.com/products/11155

These are rated @ 3A but I have used them to switch 4.5A and they usually hold up pretty well.

These are rated @ 5A but I haven't used any yet > THESE

Glad to hear you are using an enable switch and a trigger switch, that's a good safety practice. :)
 
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Thorsteenster

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Later today when my batteries get here or tomorrow I'll post a pic so you can see the switch's location.
I probably could go with a slightly bigger switch w/removing more plastic, but you will see.

That latching switch looks pretty cool, I found a couple schematics for making one but none with SMDs that I noticed.
Either way, a little more complex than I'm trying to get but I did bookmark a what I found, never know when it may come in useful!

Edit: So in waking up in the wee hours to catch the blood moon, in between going outside I started looking on Mouser for a better arming switch and came across a nice 3A one but w/shipping is about $15.
I found something similar on Amazon except 2A but the same size as Mouser's switch. Bigger than what I have now so it'll take a little more work to mount, but the increased robustness over the initial switch will definitely help with durability.
 
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