Prop 2, RC4 and e-crackers

[Jeff Haas]

I just got some of those electronic crackers - they're designed to look like Chinese firecrackers, but they plug into the wall and make a loud popping sound as long as you leave them on.  Here's a link to a YouTube video: http://www.youtube.com/watch?v=39VS9Y29ywQ  These are much louder than the impression you get from the video!

I think they'll find a good place in our lab, we're going to have a Jurassic Park-type lab where all the animals have broken out.  But I'd like to run these as safely as possible, so I've ordered an RC-4 to work with my Prop 2, along with a couple of relays, a pigtail for the power and a connector.

Question: What should all this be mounted in?  Is there some kind of standard electrical box at a hardware store which will work?  And since I'm going to do some minor wiring to connect up the electric crackers, can I get some advice on the best way to do that?

The crackers come with a standard 110V plug, and there's a switch that toggles the "cracking" on or off.  I figure I should be able to leave the switch on, then wire an electrical outlet so that it's connected to the RC-4 and toggle the relays to create the effect.

Any help on this is appreciated, I haven't worked with line voltage on this type of project before.  Once I get the wiring taken care of, then I'll deal with the software.

Jeff

[livinlowe]

That is an interesting device. I wonder how it makes the poping sound. Anyway, if you want to wire this up in a metal junction box, that would work. As far as wiring, if you look at the plug on the device, the smaller prong on the plug is the 'hot' prong. How far away is the RC-4 going to be from the firecrackers? The safe bet would be buy some flexible metal wiring and wire that to the rc-4 and terminate the wiring in the metal junction box near the firecrackers. Your "really" safe bet would be to bribe a buddy who is comfortable with working with 120V AC to help you out. If you don't know what Im talking about when I say flex metal wiring, just go to home depot and ask a sales associate. They should be able to help you. You can use ROMEX wiring to do this, but flex metal is "safer" because the wire is in its own conduit. Be safe.

[bsnut]

Shawn is pointing you in right direction and since I am maintenance electrician. I will help you out here for how its connected to 120VAC outlet "receptacle"

120VAC outlets "receptacles" have 3 connections on them, "Hot" (dark colored srew), the "Neutral" (silver colored srew) and the "Ground" ( green colored srew)

Now you will need to hook up the RC-4 to the receptacle.

1. Take a black wire from one of the RC-4 K1 terminal block srews to the receptacle's dark colored srew

2. Take a black wire from the last RC-4 K1 srew on the terminal block to you plug's dark colored srew, which is the "Hot".

3. Take a white wire from the silver colored srew on the receptacle to the silver colored srew on the plug.

4. Take a green wire from the green colored srew on the receptacle to the green colored srew on the plug.

Remember the 120VAC should all be enclosed in a electrical box. If you want, you can use a plastic electrical box for your receptacles. But, remember to connect the green colored srew on the receptacle to the green colored srew on the plug.

I will post a basic drawing later on today.

[Jeff Haas]

Thanks guys, this is just what I'm looking for.  I'm going to mount the box close to the crackers and have a push button on top of the display for the haunt tour guide to press, this will go to the Prop-2 which will trigger the FC-4.

bsnut, What kind of wire do I get for this? 

[bsnut]

Jeff,

I am going answer this question for you.

What kind of wire do I get for this?

You will need #14 AWG (American Wire Gage) stranded or solid minimum or you can also use wire from extension cords. 

The best thing for you to do, is to make your own extension cords (one for each relay on the RC-4) without the male plug and take the female end (receptacle end) using SJO cord and take the end of SJO cord and connect it a 6" x 6" x 2 1/8" deep plastic junction box where the RC-4 will be mounted in. SJO cord and the plastic junction box can be pickup from your local hardware store like Lowes, or Home Depot, or ACE Hardware.

BTW You can use the drawing that is in the RC-4 PDF to go by for wiring things up. Remember to replace the lamp in the drawing for a receptacle.     

[Jeff Haas]

Thanks, William.

I took another look at the RC-4 PDF.  Where is the picture with the lamp in it?

[bsnut]

Jeff,

Just remember to strip back enough jacket on the SJO cord (any other cable that you chose) to make all the connections, mainly on the white wire "neutrals" and the green wire "grounds", so you don't block the Solid State Relays   

[Jeff Haas]

I'm happy to say that I got the package from EFX on Thursday, spent some time over the last couple of days reading docs and putting things together, and after some code tweaking, it's working well.  I've got a button that triggers a sound effect played back via a speaker and then the crackers go off, as if something has shorted out.  Very nice effect!

The "embryo chamber" is in its early stages and is starting to look good.  Video of the final setup will get posted in the completed projects forum.

[bsnut]

I am glad got everything working.

[Jeff Haas]

Just wanted to say thanks again for the help.  We ran our mad scientist haunt this weekend, and the "computer control panel" with a red button that set off the Prop-2, the RC-4 and the crackers was a BIG hit - one of the stars of the haunt.  The crackers were originally just supposed to wake up a sound-activated monster embryo in a big tube, but they ended up setting off every sound-activated prop in the yard.  So chaos reigned for a moment, and really startled the crowds.  Some friends took video of the whole haunt, when I get it I'll put up a clip and link to it in the completed projects section.

There's nothing like having a reliable, automated part of the show!