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Turn a light bulb on with every new user or download

rigoneri.com

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Re: Turn a light bulb on with every new user or download

#11
BIG FAT WARNING: If you're going to relay your Raspberry Pi / Arduino to mains electricity, be very, very careful!

Mains electricity can KILL. Make sure you learn about safe shielding, connecting and grounding practices.

Above all, be extremely cautious!

I can't stress this enough.

EDIT: For more information: http://tubelab.com/Safety.htm

Re: Turn a light bulb on with every new user or download

#12
post #4

This seems like a really great use for raspberry pi. I recently finished a project involving a pi + a relay to activate a door buzzer, written in javascript. It was surprisingly simple and straightforward. Besides turning on lights, the cool thing about relays is that most things involving physical push-buttons can be taken apart and easily wired up to a relay.

What protection do you use for the Pi's GPIOs?

[deleted]

Re: Turn a light bulb on with every new user or download

#14

For a larger company with more signups/uploads, I'm envisioning a wall of LEDs, controlled by an Arduino board.

Not quite the same, but your description reminded me of Movable Type, the installation in the New York Times building:

http://www.screenmediadaily.com/technology-movable-type-new-...

Re: Turn a light bulb on with every new user or download

#15
post #13

Working with mains power is stupid. Don't do it if you can avoid it, especially if you don't know what you are doing. You can get a small remote power switch for $100 or so.

Belkin WeMo is only $49 and programmable via IFTTT.

Edit: $45 on Amazon at present.

Re: Turn a light bulb on with every new user or download

#16
post #11

BIG FAT WARNING: If you're going to relay your Raspberry Pi / Arduino to mains electricity, be very, very careful! Mains electricity can KILL. Make sure you learn about safe shielding, connecting and grounding practices. Above all, be extremely cautious! I can't stress this enough. EDIT: For more information: http://tubelab.com/Safety.htm

Better yet: Don't connect your Raspberry Pi / Arduino at all to mains electricity unless you use an opto-isolator, or you have training in designing such circuits.

The usb relay is NOT designed for this! See the picture: http://www.circuitgizmos.com/products/cgu451/cgu451.shtml

In a device intended for hybrid hi/low voltage there is a clear gap between the high and low voltage components, and an isolation transformer or opto-isolator between them.

Re: Turn a light bulb on with every new user or download

#17

For a larger company with more signups/uploads, I'm envisioning a wall of LEDs, controlled by an Arduino board.

Or better yet, make it interactive with something like this: http://shop.evilmadscientist.com/productsmenu/majors/150-pan... Peggy's could be fun too: http://shop.evilmadscientist.com/productsmenu/tinykitlist/75...

The Peggy 2 looks really neat. I just might spend some time on this during the summer...

Re: Turn a light bulb on with every new user or download

#19
post #16
post #11

BIG FAT WARNING: If you're going to relay your Raspberry Pi / Arduino to mains electricity, be very, very careful! Mains electricity can KILL. Make sure you learn about safe shielding, connecting and grounding practices. Above all, be extremely cautious! I can't stress this enough. EDIT: For more information: http://tubelab.com/Safety.htm

Better yet: Don't connect your Raspberry Pi / Arduino at all to mains electricity unless you use an opto-isolator, or you have training in designing such circuits. The usb relay is NOT designed for this! See the picture: http://www.circuitgizmos.com/products/cgu451/cgu451.shtml In a device intended for hybrid hi/low voltage there is a clear gap between the high and low voltage components, and an isolation transformer…

I have training in designing such circuits and I'd still use an opto-isolator.

This is not manufacturing. It's a one-off project. It's not a highly refined design. You don't have to worry about finessing a marginally lower build cost because of what it will mean in 10k unit quantities. Just use the opto-isolator.

Re: Turn a light bulb on with every new user or download

#20
post #4

This seems like a really great use for raspberry pi. I recently finished a project involving a pi + a relay to activate a door buzzer, written in javascript. It was surprisingly simple and straightforward. Besides turning on lights, the cool thing about relays is that most things involving physical push-buttons can be taken apart and easily wired up to a relay.

Arduinos can (supposedly) host webpages, and pins can be powered or depowered by (properly parsed) HTML POST commands. Combining this with a relay means we can create WIFI website interfaces for anything that uses electricity. The opportunities to improve current products are so endless that I become overwhelmed whenever I think about this. We all have the parts to do this today, but so few are assembling them. --- W…

Couldn't agree more. I wrote a blog post about it a while back demonstrating my take on this. Here's common household appliances getting web interfaces that can be accessed with any smartphone by QR Code. No arduino or soldering mains current required. I think every electronic thing in my house should have a little QR Code next to it so I can just point my phone at it and get its interface.

http://www.thesinglestep.org/thoughts/qrcontrol/

The video halfway down shows it in action.

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