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220v/110v AC Power connector controled by the computer.

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January 28, 2008 11:53:35 AM

This is a very easy, simple and useful mod to do if you have some basic soldering skills.
I meant useful because it is for me, and who knows maybe for some of you.
When i turn off my computer i have to turn off my 2 monitors (so they dont keep the power led blinking for ages till the next i use the computer), turn off my stereo, a little amplifier for my headphone set and sometimes my little chandeleer that i only use when im using the computer. That's a lot of things to turn on or off when i using the computer or not.
The solution is really simple. You'll only need a small device called relay, and it looks something like this:



or this:


(mine looked more like this one)

But it can take various forms for what it's worth, its really unexpensive, mine costed 2€ more or less, and with it you can make a AC power connector like this:





to be turned on or off whenever your computer is working or not.


Let me just explain the pinout of this component:

1- 5Volts or GND
2- 5Volts or GND
3- Power connector interrupt 1
4- Power connector interrupt 2
5- Unused


Pins 1 and 2 are the juice for the component. The polarity is irrelevant, it will work either way. A 5Volt relay would be ideal for this little mod.
Pins 3 and 4 are the switch for your power connector.

Without trying to insult the intelligence of those who already got the ideia or totally understand how this kind of stuff works, im going to explain how this component works under these circumstances for a better understanding of those who don't.
It's pretty easy actually, when the computer is on, it juices the relay in those pins (1 and 2) powering a small electroiman inside of it, creating a small magnetic field like real imans and pushing away the little iron piece that you see in direction of pin 4, making it touch the sorrounding pins (depending on how the relay in question was manufactured) closing a circuit and allowing current to pass through.
When the computer shuts down, the relay stops working opening the circuit and everything connected in the power connector will shut down as well, saving electric power.
For example, most printers even when computers are turned off, they're still wasting small amounts of power because they're still connected (if you touch their transformers you feel them somewhat hot, that way if you connect them too this mod, it will save power.)

This is one possible aplication, but it can have some particular aplications of your own.
You can even have the reverse effect by simply connecting pin 5 instead of pin 3.

The final result would be something like this:




You must make sure that you do a good soldering job because if one of the power connector wires gets loose and touches pins 1 or 2, it can blow the relay or even worse, explode your PSU or the whole computer..
So do this at yours own risk.
If you have good soldering skills but you're still afraid of something like this happening, use some duct tape to trap the wires.

The aplication:


As you can see, there is a wire getting of the power connector going directly to a psu floppy connector, using its 5 volts to power the relay, but i'm about to make this more practical, and connect it to a usb or a com port (i only need a usb or com plug) and get the 5volts from there.

You can connect other power connectors to the one you just modded if you want to make more devices to be dependant on your computer.



But be warned, if you connect too much devices to them, mostly high wattage devices like several monitors or lots of light bulbs you may murder the poor relay.

So this is about it. I know this isn't a subject of interest to most of these forum readers, but i thought it would be interesting to share some easy_to_aquire_knowledge, this it pretty easy to assemble, there is no need for any sort of special software or any geek knowledge and can be very useful in some cases.
Thanks for reading for all of those who had the patience to read this all the way through. :) 
Greets.
January 28, 2008 1:29:18 PM

Man, ever since the day I bought my huge and noisy Hydor L30 I wanted to build a relay-based powerswitch to turn it on and off together with the computer.

That was six months ago...
"Hard work pays off in the future. Laziness pays off now"


Anyway, great guide. Had no idea I could reverse the effect.

If only there was a way this easy to power Off that damned dog when I go to sleep.
January 28, 2008 4:58:46 PM

Thanks, this isn't anything that special, and it's somewhat easy to acomplish, and yeah, i was planning this for a long time too, but lazyness was owning me big time.
Reverse effect is possible and even simultanious effects are possible too, if your relay has double switch. Mine did.
About the dog..replace it with a AIBO dog :D 
Related resources
January 28, 2008 6:19:49 PM

I'm actually using a remote-controlled power switch to start/stop the pump manually.

The only downside is that I forget to turn it on once every week and the damn water starts to boil. (Hotd0gs, anyone?)


Why not this d0g? (He's the one on the left, by the way...)
http://upload.wikimedia.org/wikipedia/en/9/9f/HalfLife2_Dog.jpg
He'd probably make more of a mess than the AIBO...

And, about the one on the right...
Spoiler
I'd hit it.



Back on topic:

About how much power can your relay safely handle before it turns into a flaming cloud of entropy?

Maybe relay-modding would become the latest trend in PC-modding - In a year or two, we'll probably be seeing tonnes of relays glowing like a Christmas tree. :bounce: 


Guess I'll go relay-shopping tomorrow. ^^
January 28, 2008 9:43:51 PM

Snillet said:
About how much power can your relay safely handle before it turns into a flaming cloud of entropy?


I can't recall correctly how much wattage it can handle, only that is more than enough for what i'm using at the moment.
Anyway, thats something you can pick when buying one.
January 28, 2008 10:53:38 PM

In general, I do not recommend that anyone messes around with high voltage wiring such as this. The voltages are lethal, and there is enough current available to vaporize offending pieces of metal. If you insist on undertaking such a project, please be careful, and as a minimum, note my advice below.

A safer way might be to use the X-10 control system, and use the plug-in relay appliance control module. This is more expensive, but it gives you lots of options (remote control of lights, etc.).

For those of you with a death-wish, read on. . .

The top picture shows a SPDT (Single-Pole, Double-Throw) relay. The next picture shows a DPDT (Double-Pole, Double-Throw) relay. Single-pole refers to the fact that the relay can switch one circuit; a double-pole relay can switch two independent circuits. The "Throw" refers to the number of positions each set of contacts have; a single-throw contact is either on or off. A double-throw contact can switch the common line to either one of two contacts, "A-on/B-off" or "A-off/B-on".

For a 240VAC circuit, be sure and use a Double-Pole relay to switch both "hot" lines, or you will leave one side of the circuit "hot" when you switch the other side off.

For a 120VAC circuit, you can use a Single-Pole relay, but be sure and connect it to the "hot" side of the line; this is typically the black wire - the one connected to the small blade of the plug.

Be sure and select a contact rating that is suitable for use in this manner. In the US, a standard 120V AC receptacle is on a 15A breaker; use a relay with at least a 15A contact rating for safety.

If you exceed the relay's contact rating, you run the risk of fire. Likewise, make sure you are driving the relay coil with sufficient voltage & current, or the contacts will not close with enough force to maintain a low resistance closure.

Finally, I didn't see any kind of circuit breaker or protective device in the power strip the OP used. This is a very dangerous power strip, and I would get rid of it for that reason. Likewise, there are no surge-protection components in the strip.

Since you can buy very good power strips with circuit breakers and surge protection - and ON/OFF switches, I might recommend that instead. It's not too much trouble to reach down and switch off the power strip. This also keeps you from killing yourself when you are messing with dangerous high voltages.

Altazi, electronic design engineer
January 28, 2008 11:35:21 PM

Choosing what kind of Power strip to use is up to everyone to do, it' isnt obviously mandatory to use the exact type of powertrip showed in the picture for this kind of ideia to work.
The X-10 control system is pretty good in comparation (comparation lol, it can not nearly be compared aside the main ideia of it), but the ideia was to do something similiar (obviously without so many options), and for a incredibly cheap price.
High voltages are risky, so again whatever "you" do, do it at your own risk. I didn't point that because it would be pointing the obvious, that's a opened powerstrip we have there gentleman :D 
What i really should have mentioned was this:
altazi said:
For a 240VAC circuit, be sure and use a Double-Pole relay to switch both "hot" lines, or you will leave one side of the circuit "hot" when you switch the other side off.

You're absolutely right about this, it's much safer this way!

Again, i dont want to set anyones house on fire, i just wanted to share an ideia, and now it cant be more detailed than it already is here, so have f00n ;) 
January 28, 2008 11:39:39 PM

Damn double post, couldnt delect it :fou: 
January 29, 2008 12:34:37 AM

Hi rickzor,

I'm sure YOU know that these high voltages are dangerous, but you can't be too obvious in cases such as this. I have seen a wide range of technical ability and knowledge in these forums. There are some who don't know that thermal compound (or at least a thermal pad) is required between the CPU and the HSF. My warnings are for people of that sort. Nothing wrong with not knowing something, but learn before burn, eh?

Altazi
January 29, 2008 12:55:07 AM

rickzor said:
This is a very easy, simple and useful mod to do if you have some basic soldering skills.
I meant useful because it is for me, and who knows maybe for some of you.
When i turn off my computer i have to turn off my 2 monitors (so they dont keep the power led blinking for ages till the next i use the computer), turn off my stereo, a little amplifier for my headphone set and sometimes my little chandeleer that i only use when im using the computer. That's a lot of things to turn on or off when i using the computer or not.
The solution is really simple. You'll only need a small device called relay, and it looks something like this:

http://www.donosgune.net/2000/irudiak/rele.jpg

or this:

http://www.msebilbao.com/tienda/images/RELE1.jpg
(mine looked more like this one)


Uh... Wouldn't the switch on your outlet be easier?

Nice mahogany table / bench / desk though.
But it can take various forms for what it's worth, its really unexpensive, mine costed 2€ more or less, and with it you can make a AC power connector like this:


http://img528.imageshack.us/img528/5594/extensao0ef.jpg


to be turned on or off whenever your computer is working or not.


Let me just explain the pinout of this component:

1- 5Volts or GND
2- 5Volts or GND
3- Power connector interrupt 1
4- Power connector interrupt 2
5- Unused


Pins 1 and 2 are the juice for the component. The polarity is irrelevant, it will work either way. A 5Volt relay would be ideal for this little mod.
Pins 3 and 4 are the switch for your power connector.

Without trying to insult the intelligence of those who already got the ideia or totally understand how this kind of stuff works, im going to explain how this component works under these circumstances for a better understanding of those who don't.
It's pretty easy actually, when the computer is on, it juices the relay in those pins (1 and 2) powering a small electroiman inside of it, creating a small magnetic field like real imans and pushing away the little iron piece that you see in direction of pin 4, making it touch the sorrounding pins (depending on how the relay in question was manufactured) closing a circuit and allowing current to pass through.
When the computer shuts down, the relay stops working opening the circuit and everything connected in the power connector will shut down as well, saving electric power.
For example, most printers even when computers are turned off, they're still wasting small amounts of power because they're still connected (if you touch their transformers you feel them somewhat hot, that way if you connect them too this mod, it will save power.)

This is one possible aplication, but it can have some particular aplications of your own.
You can even have the reverse effect by simply connecting pin 5 instead of pin 3.

The final result would be something like this:
http://img296.imageshack.us/img296/8380/ass1al0.jpg

http://img176.imageshack.us/img176/8504/ass2kc0.jpg

You must make sure that you do a good soldering job because if one of the power connector wires gets loose and touches pins 1 or 2, it can blow the relay or even worse, explode your PSU or the whole computer..
So do this at yours own risk.
If you have good soldering skills but you're still afraid of something like this happening, use some duct tape to trap the wires.

The aplication:

http://img86.imageshack.us/img86/6638/img0063mt8.jpg
As you can see, there is a wire getting of the power connector going directly to a psu floppy connector, using its 5 volts to power the relay, but i'm about to make this more practical, and connect it to a usb or a com port (i only need a usb or com plug) and get the 5volts from there.

You can connect other power connectors to the one you just modded if you want to make more devices to be dependant on your computer.

http://img144.imageshack.us/img144/6330/img0065ac3.jpg

But be warned, if you connect too much devices to them, mostly high wattage devices like several monitors or lots of light bulbs you may murder the poor relay.

So this is about it. I know this isn't a subject of interest to most of these forum readers, but i thought it would be interesting to share some easy_to_aquire_knowledge, this it pretty easy to assemble, there is no need for any sort of special software or any geek knowledge and can be very useful in some cases.
Thanks for reading for all of those who had the patience to read this all the way through. :) 
Greets.

January 29, 2008 10:14:21 AM

LOL, i was actually lucky to find this inside the whole quote, you shouldn't talk inside the quote, i nearly missed it.

"Uh... Wouldn't the switch on your outlet be easier?

Nice mahogany table / bench / desk though."

The switch would kill the main essense of the thread, "220v/110v AC Power connector controled by the computer."

As for the "mahogany table / bench / desk though", it's actually a floor :p 
January 29, 2008 3:51:13 PM

Wow, you have better eyes than I do. I was puzzled at what looked to be a copy of your entire post, and nothing more.
!