1. Wiring the Light and Relay

2. Caution!!!
In this section we will be working with 120v AC (wall outlets)
DO NOT touch exposed wire when circuits are attached to power
Be mindful of which sections of the relay are low voltage vs. high voltage as miss-wiring may result in shorted out devices or electric shock

3. Relays 101 Relays come in two types: Mechanical and Solid State
We will use a mechanical relay
Mechanical relays use a magnet to switch the circuit
This allows for low voltage to control high voltage circuits
We will be using the JZV-11F relay
Datasheet available on course site

4. Analyzing the Datasheet
We can see on page 3 that there are 5 pins
The 2 at the bottom are attached to the magnet. According to the sheet they rated for 12V
The 3 pins are the switch
One side is normally open while the other is normally closed
This refers to the state when the magnet is not energized
The diagram shows us that the lone pin is the common while the two diagonal are the switched pin
We want to connect our lamp to the normally open pin (the top one) so that the light will default to being off

5. The relay

6. Stock puck light

7. Add 2 prong plug to the end of the cable

8. Slide on the cover to push wire on pins

9. Test the lamp Plug the two prong plug into the outlet
The light should turn on
It is important to test the lamp before introducing the relay to the circuit to make debugging issues easier

10. Cut off the extra wire leaving about 6 inch long leads from the light

11. Strip about ½ inch from the ends

12. Slide 1” of heat shrink tubing on each wire

13. Prep the socket from the power supply so the black and white wires have free ends

14. Strip ½ inch from the end of the black and white wires

15. Pass the white wire through the square socket hole (since the socket goes on the outside and the lamp on the inside)

16. Twist the white wire with one of the leads on the lamp, solder the connection, then cover with heat shrink tubing

17. Twist the black wire to a 6” piece of extra wire and solder (not the second lead of the lamp!)

18. Cover with heat shrink

19. Solder a wire to each of the low voltage pins (a picture of a coil appears above them). Take the extension to the black wire and place it on the common pin of the relay. Be sure to place a piece of heat shrink on the wire before making the connection.

20. Solder the connection and place the tubing over the joint
Solder the connection and place the tubing over the joint. Also place a piece of heat shrink tubing on the normally closed pin to insulate it

21. Solder the second lead from the lamp to the open pin on the relay (again remember to put heat shrink on the wire before connecting)

22. After soldering and heat shrinking the final connection, wrap the plug in electrical tape covering all connections

23. Do the same for the relay

24. Mount the plug back to the power supply

25. Adhere the lamp to the chamber bottom using hot glue
Adhere the lamp to the chamber bottom using hot glue. Be sure to leave space for the small internal breadboard when positioning

26. Testing Time
We will be using our Arduino as a 5 volt supply and the wall outlet for the 120 volt source
When energizing the relay (completing the circuit between the 5 volt output and ground with the low voltage leads) one should hear a clicking sound. This is normal and is the sound of the magnet moving the bar which completes the circuit

27. Power Cable

28. Attached to 120 Source

29. Ground Lead attached to Arduino

30. Connecting the other lead to the 5 volt port will turn the relay on and control the lamp (remove either lead to turn it off)