Need power/voltage advice

Hello,

I am looking into making a board that will and turn on either a red or a green beacon light over wifi, these are the beacons I will (possibly) be using:

http://www.amazon.com/gp/product/B005UVYEOW/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=AWA6OAR05Q5HX

I will be using:

Adruino UNO R3
Arduino WiFi Shield
SainSmart 4 channel Signal Relay for Arduino UNO R3 MEGA2560 MEGA1280
Breadboard jumper wire 75pcs pack

I have no idea how I will supply power to these to beacons from this board/relay. I am very new to this. Any help would be GREATLY appreciated.

Thanks in advance.

How are the beacons powered normally? Batteries or a DC adapter?

If the latter then you may simply be able to cut one of the wires between the adapter and the beacon and splice in the relay. However you need to know that the relay is rated for the voltage and current of the beacons. I'm not sure what else there is that can be said without more information.

Thanks for your response Dr_Ugi.

The beacons are not battery powered, the Amazon listing says: For Red beacon: 5' long black UL Listed power cord, and for Green beacon: A/C Adapter Included. (They seam to be the same beacon, different colors, different sellers)

Is there a specific relay I should purchase for this type of power? Again, I apologize for my inexperience.

Again, it's hard to tell without knowing the rating of the beacons but i would expect a basic relay module of this type:

http://www.ebay.co.uk/itm/390517866900

Would do the job. It's rated to something like 30V & 10A DC. I can't see how your beacon can be much above 12V or 2A but that is an absolute guess.

You could probably do equally well with a transistor (maybe a darlington or MOSFET) but for that you probably would need to know more about the specifications of t bacon.

Edit - equally, your sainsmat relay appears to be rated to 30V 2A. You can't know for sure without knowing the rating of the beacon but I would doubt it takes more than 2A and I'm sure it won't go above 30V.

Great, thank you very very much for your help, can't thank you enough. Also, would I be able to power this board (Arduino UNO R3 with everything connected) with a battery? If so how would I go about doing that?

Thanks!!

You can power your ardiono from a 9V battery. Actually the Arduino has a voltage regulator that allows you to use a range of input voltages.
Even 12V is possible, but not recommended. If the beacons should run of, lets say, 12V, then I would just take those 12V, but in a voltage regulator 12V->9V and run the Arduino of that.

The advantage is that you never need to change the battery.
There are also other voltage regulators that allow regulation to 9V from higher voltages (in case the beacons run at higher voltages).
Popular voltage regulators are the LM7809 series (just google for them).
The Arduino usually uses so little current that one beacon power supply should have no problem to power beacon and Arduino.

here is a picture of a potentail setup. really just a rough sketch.....
basically you cut ther + from the beacons and wire both to relays. those relays get switched by the arduino.
On one power supply you also hook up a voltage regulator that powers your arduino. the ground of all devices must be connected.

Thank you very much for the advice and diagram, very helpful!!