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How do I safely connect a micro switch to a 6 outlet power supply? Answered

I have the Big Dome Push Button (sparkfun electronics) so I can start the power for an arcade machine with a press of a colorful lighted button. However, I'm new to the hobby of electronics so even this simple build is confusing to me. I basically need to connect the micro switch and LED  to a typical 6 outlet power supply. Help!



Best Answer 4 years ago

OK here is a circuit designed just for you !

You will need a DPDT Double Pole Double Throw 12VDC coil relay that can switch 5 amps at your mains voltage and a 12VDC wall wart plug in supply and a diode to help avoid voltage kick back.

The big advantage of a relay is that a safe low voltage like 12 Volts DC

can control DANGEROUS 120 Volts AC !!!!

Later you will need a SPDT switch and an LED and a 1000 ohm resistor.

The relay can be tested without the HIGH VOLTAGE SIDE plugged in and make sure it works before you test with your high voltage side activated.


Wow, thanks so much iceng! I'll be working on this as soon as I can!

Follow up... Ok, I guess turning on a power strip with a big push button isn't as easy as I thought. It's a shame 'cause I'd look really cool. Anyway, I would still like to have the on/off button more accessible than directly on the power strip. Would this https://www.sparkfun.com/products/11971 work?

Follow follow up... where is a good place to start for learning electronics as a hobby ( as a noob, lots of pictures would help)

Thanks for all the replies. Basically I have learned that I need a relay switch for this to work. So my next question is...were do I find a diagram for a micro switch + an LED to a relay switch to a 6 outlet power supply? (Where the purpose is to switch the power supply on/off with a big red button instead of the on/off switch on the power supply)


4 years ago

No Safe way for you until you get some knowledge of electric circuits

and some experience in your new hobby

This is going to sound like a dumb question, but, erm, supposing pushing the Big Dome Push Button causes the arcade machine to become turned on, by what way how are we expecting to turn the arcade machine off? Could it be that pushing the Big Dome Button a second time, whist the arcade machine is on, causes it to turn off? Or is there a second Big Dome Button for to turn it off? One big button turns machine on. Another big button turns it off.

I mean, either way, these sorts of things are doable, but require moar circuits than just the push button(s) alone. Like Steve says, this can be done with relays.

The only way to do this needs relays and your switch

If your switch is the kind of switch I think it is, then, by itself, it is not suitable for switching AC loads for two reasons.

(1) It is a momentary switch; i.e. the load would only be powered while the button is held down.

(2) It is likely not made to withstand the voltage across it when open, or the current that must flow through it when closed.

By the way, the product description on this page:


says the "microswitch" part of the big button is replaceable, which to me says it is possible to examine that switch up close. Doing so may reveal some markings left there by the manufacturer, for the purpose of letting you know about the specs of this switch, the maximum rated voltage, maximum rated current, that sort of thing.

Also BTW, I think the word "microswitch" is a genericized trademark, and the actual generic name for this kind of switch is "miniature snap-action switch"


The Wikipedia page is worth looking at, because you can compare your itty-bitty three-terminal switch to the ones in the pictures, so as to confirm that it is, or is not, that kind of switch.

Let me understand this correctly. You want to replace the power switch on a 6 outlet power strip right? And the switch you plan to use is an arcade style switch correct? Unless that is a latching switch that can handle 120VAC (assuming USA) and about 10A (which i highly doubt) you won't be able to use that switch. If the switch can handle that you'll still need a cricuit to take the 120VAC and reduce it down to about 3VDC to light the LED.