Little help getting started with my little project.

Hi guys,

I'm completely new to Arduino and having ordered my board can't wait to do some experimenting. My first project is to add LEDs to my son's toy kitchen. It would have up to 8 LEDs and 3 magnetic switches. The idea is to lit a led or two when oven / microwave / cupboard door opens. Once that mastered I want to add photo sensor so the whole thing lights up when it gets dark, the last bit would be adding remote control to control LEDs but let me ask you probably a silly question first. When connecting series of LEDs to breadboard each LED positive leg is connected to Arduino pin and negative to GND - of course there is resistor between. GND is connected to one of the lines on breadboard so every LED's negative leg is connected to that line. I won't be using breadboard - each LED would be soldered to a resistor and then connected to specific pin on Arduino. Am I understanding it right there will be one wire connected to GND and all the negative connections (from LEDs and magnetic switches) would be connected to that single wire ? Am I thinking right ? I don't want to fry my board by doing something fundamentally wrong. I know is must sound silly to you but I seriously am newbie here :) Thanks for your help.

zebik: Hi guys,

I'm completely new to Arduino and having ordered my board can't wait to do some experimenting. My first project is to add LEDs to my son's toy kitchen. It would have up to 8 LEDs and 3 magnetic switches. The idea is to lit a led or two when oven / microwave / cupboard door opens. Once that mastered I want to add photo sensor so the whole thing lights up when it gets dark, the last bit would be adding remote control to control LEDs but let me ask you probably a silly question first. When connecting series of LEDs to breadboard each LED positive leg is connected to Arduino pin and negative to GND - of course there is resistor between. GND is connected to one of the lines on breadboard so every LED's negative leg is connected to that line. I won't be using breadboard - each LED would be soldered to a resistor and then connected to specific pin on Arduino. Am I understanding it right there will be one wire connected to GND and all the negative connections (from LEDs and magnetic switches) would be connected to that single wire ? Am I thinking right ? I don't want to fry my board by doing something fundamentally wrong. I know is must sound silly to you but I seriously am newbie here :) Thanks for your help.

Welcome to the Arduino forum. You are on the correct track learning how to connect and program for one device at a time.

Which Arduino board? Makes a difference.

Soldering is fine, but for LEDs, when you solder the wire leads, use a pair of needle nose pliers right next to the LED body so heat from soldering doesn't damage the diode inside. That's why a breadboard is great for learning and development.

The magnetic switches are most likely reed switches, like your see on doors that are alarmed. If you can make sure you have a bar magnet and it should be parallel to the axis of the body of the reed switch.

Paul

zebik: Hi guys,

I'm completely new to Arduino and having ordered my board can't wait to do some experimenting. My first project is to add LEDs to my son's toy kitchen. It would have up to 8 LEDs and 3 magnetic switches. The idea is to lit a led or two when oven / microwave / cupboard door opens. Once that mastered I want to add photo sensor so the whole thing lights up when it gets dark, the last bit would be adding remote control to control LEDs but let me ask you probably a silly question first. When connecting series of LEDs to breadboard each LED positive leg is connected to Arduino pin and negative to GND - of course there is resistor between. GND is connected to one of the lines on breadboard so every LED's negative leg is connected to that line. I won't be using breadboard - each LED would be soldered to a resistor and then connected to specific pin on Arduino. Am I understanding it right there will be one wire connected to GND and all the negative connections (from LEDs and magnetic switches) would be connected to that single wire ? Am I thinking right ? I don't want to fry my board by doing something fundamentally wrong. I know is must sound silly to you but I seriously am newbie here :) Thanks for your help.

Hi zebik, In elecrtical circuits you will always have a complete path from and back to your supply. You can do this by running a seperate loop for each device or you can run one common wire around your project usually the earth. This is because in electrical cabinets and say vehicles they are made of metal and it is easy to wire the earth to the cabinet but this was done for several reasons one being reduces expense. Did you know that there were posative earth vehicles around pre 1990? Use to be hell fitting new stereos to them

For this project you will find it easier to fit the leds to the end of some speaker cable, cutting one leg of the led shorter and fitting the resistor in its place then connect the wires and cover with heatshrink. This way when they exit the doll house you will have one wire set for each led. You can then connect the earths to a buss bar or earth strap making them all common and connect that to the Arduino.

Beware! Check the Arduino specks and make sure you do not overload it when you have all the leds running and check the max each pin can provide so as to know what resistor value you need.

Once you have the setup going you can experiment with dimming the leds you connect to the PWM ports on the Arduino but first just start with ON/OFF.

Also keep in mind that if fitting even the smallest led or the wiring into the house is a problem, move the led elsewhere and run a fibre optic cable in its place. Takes a bit of fiddling to fit the led to the fibre but is sometimes easier to run a cable that is 0.5 mm thick from start to finnish.

Control panels with on/off and dimming knobs fitted to an external control box are fun to although i have heard of people building working minature light switches.

You ma

Big + on the use of heatshrink tube to cover & seal wiring! Electrical tape does not cut it for finished work once you know the difference.

An Arduino that has pins that can plug into a breadboard, those pins can also take female jumper ends. I get DuPont Cables, 20 or 30 cm flat rainbow color cable with th wires at both ends given separate ends with either pins or holes. I peel as many wires as my custom cable needs and my jumpers don’t rat nest quite so quickly.

The 1st few things on the OP’s list don’t need a controller. A led + resistor + switch + power will do some of the kitchen lights and important part here Daddy is to play that out while you get background and maybe find a good working project that does what you want,

A lot of what I will do to help depends on what you’re in this for. You’re not in this for a grade, for instance but do you want to learn well enough to make future projects even to real house automation? That is a hill to climb but many of us know the paths up well.