I don't know what is the difference between those two 8 channel relays. Right now I just want to select which device I want to turn on. I might add wifi on arduino so I can control with my small tablet. I hate to use power strip to turn on everything on but I don't use all of them. Can someone give me some advice on this?
The first is a mechanical relay which works by an electro magnet causing two contacts to be brought together.
The second is an electronic switch with no moving parts.
The first makes a click when it turns on and the second is silent. Either will do for your project. But the first one can switch any current up to the maximum contact rating where as the second as well as having a maximum current also has a minimum current it will switch.
For devices that will be on for hours at a time, I'd look into bistable latching relays. All of those hobby relay modules continuously suck up power just to keep the device 'on' since it's an electromagnetic coil being energized that holds the switch.
Hell I'd be more inclined to hook up solenoids to manually move rocker switches before resorting to using those hobby relays for most applications.
I want it to be more easier for my wife or grand kids to select which one that need to turn on and use it. Not turn all devices on (Xbox, PS3, Wii, DVD player and tuner). When I am gone and my grand kids or great nephews or nieces come over to my house and they want to watch TV show or movie or play games. My wife will have hard time to find which one that need to turn on to play games or watch TV or watch DVD movie. She wish we can make it simple. I thought I could make an app for small tablet with several button for her to click on. Example first button for play game with mean just turn on the TV and Xbox to play games, second button for watch movie which mean turn on the TV and DVD player etc... I hate to use power strip which turn all the devices on at the same time if we don't use all of them. I hate waste electric and wear them out.
How many of these items have a latched power ON? It won't do much good if you have to turn on the relay first, then go and hit the ON/OFF button of the device you want to use. In fact, it might just make it more complicated
Not to mention all of those game systems are able to be turned on by the game controller. So using a tablet to turn them on via relays (which you can't without hacking power buttons anyway) is misguided.
And why does your wife need to turn things on? Those younguns know how to operate the electronics, probably a whole lot more than you give them credit for.
INTP:
And why does your wife need to turn things on? Those younguns know how to operate the electronics, probably a whole lot more than you give them credit for.
Thinking about it, maybe it's not to "turn them ON", but to anonymously turn them OFF.