This Instructable is mostly about how to build the relay box, but the end result is a cool Halloween decoration. The great thing about the relay box we are going to build is that it can be used for any holiday light show. Can anyone say Christmas lights plus Trans-Siberian Orchestra ?
Total cost of the project is somewhere between $50 and $100.
SAFETY WARNINGThis project involves working with live AC currents that can kill you. Be very careful. If you don't know what you're doing, get someone who does to help you. I'm not a licensed electrician. I've wired a few outlets/switches, but I am no means an expert. I'll try my best to steer you in the right direction, but I'm not infallible. Please do comment if I've left a glaring safety risk.
Step 1: How this all began ...
Another motivation for myself was to "build a better mousetrap". The guides I saw online for building the singing pumpkin rig were sufficient to get the job done, but I saw a few problems with them. Mainly, they involved wiring the pumpkin's lamp directly to the relay board. This limits the relay board to just being used for the singing pumpkin set up. I saw the potential to use it for other purposes such as a Christmas light show, or just as a fun light show to go with your music at your next house party.
The desire to make the relay board reusable as more than just a singing pumpkin rig lead me to come up with the design in image 1. I hacked up extension cords and wired them to the relays. The pumpkin lamps/Christmas lights/whatever could be plugged into the extension cords. This design worked well, except I had a few concerns with it. 1. It wasn't very portable. The cords would get twisted and it was a bit heavy from all the wire. 2. Safety. With this design, you basically had to carry the rig by the extension cords. I was concerned that this would lead too a wire being pulled out of the terminal block. You really don't want an exposed wire with wall current flowing through it anywhere near you.
It was with all those concerns in mind that I came up with the design in image 2. It's nice and portable. It uses standard wall outlets as the AC voltage outputs so anything can be plugged into it. The outlets and the relay board are mounted to the project box so there is no concern of wires being pulled during transport.
A little bit about myself as it pertains to this projectI may make building this rig look easy. I'll try my best not to take some things for granted that others may not necessarily know. I do have a bit of an advantage in the area of skills required for this project. I have a BS in Computer Science and an AS in Computer Network Engineering. While earning those degrees I took a number of electronics and programming courses. My dad worked in construction for many years and has experience in home electric wiring. He also taught a number of the electronics courses I had in college. I used him for advise while building my rig. All that being said, I'm going to make the semi-safe assumption that avid readers of this website are intelligent people, like to get their hands dirty in projects like this, and are up for the challenge.
linksThese are the guides that I used as a reference when building my rig.