Pressing the Power Strip Switch

[Omar.M]

Hello!
In a quest to fully automate my life and turn myself into a robot (just kidding), I've finally stumped myself on quite a simple mechanical problem.
What I wanted to do was control different aspects of my room using the parallel port-- lights, fan, curtains etc. Working on the lights, I did not want to use a relay to switch on power from Mains as I am not very comfortable with working with 120V of electricity.

So I devised a plan-- I have a power strip that has a switch on it. I shall plug in the lamp lights into that power strip. Now, I just need to somehow turn that switch on and off. I mean physically, I need something to either press the switch according to parallel port signals.

The switch is a standard rocker switch-- one side allows power to the plugged appliances, and one side turns them off.

I've been thinking what the best way to do this would be. I tried using a magnet attached to the switch vertically, with two magnetic actuators (took magnetic wire, wound it) placed on either side of the switch. I tried applying power to the actuators in hopes that the magnet would quickly rock one way or the other using magnetic force, but that did not work.

Any ideas would be greatly appreciated. Thank you very much,
-Omar

 

[gerty]

One way is to replace the switch in your plugstrip with a triac.
By far the easiest thing to do is X-10.The module plugs into an existing outletand can be controlled several different ways....

 

[ericgibbs]

hi Omar,

This is from another thread.
Added a couple of opto-isolators

Just drop the OPA's and drive the opto's from the port.

Eric

 

[Omar.M]

Gerty-
Thank you, a TRIAC seems like it may work, but I don't think I can find one around here. I have read about the X-10 modules but I really just would like to make this myself. I don't think I'm too far off, just need to get the buttons 'a pressin'! But if it comes to it, I may look into the X-10

Eric!
Thank you! The schematic looks quite extensive-- but from what I see, I'd be directly playing with mains, no? I'd really like to stay away from that, I don't think I'd like to risk it, if that is okay.
-Omar

 

[ericgibbs]

Omar,
If you use Triacs you will need isolation, modified drawing to show what you require..

You can buy R/C 4 channel, remote and 4 switching plug/skts for your system,
I use a couple, they work thru walls.

Eric

EDIT: the link you requested..https://www.electro-tech-online.com/threads/i-have-a-problem-in-my-sound-light-device.32045/

 

[Nigel Goodwin]

Don't dismiss relays so casually - they are cheap, efficient, VERY simple to use - and SAFE - safer than using a TRIAC!.

 

[Omar.M]

Thank you for the modifications to the circuit, Eric. It is much clearer now.
However, Nigel-- I guess you are right. Triacs are going to another quest on their own to find around here-- I am sure I can find some relays that will do the job somewhere.

So if I was going to do this-- what relay would I presumably look for? I think I'd need to do some snooping to figure out which terminal in the wall socket is ground and I'd need to find some heavy conducting wire, correct?

-Omar

 

[xxxxxxxxxxxxxx]

I would have to agree with everyone else saying it would be far cheaper and easier to switch the power electronicly. Anyhow, you could use a spring loaded solenoid with the shaft glued well onto the 'on' side of the rocker. When power is applied, the solenoid pushes the switch down, when power is removed, it flips is back up because it is spring loaded. This is pretty expensive, though.

EDIT: It would probably be better if you just get a non-spring loaded solenoid and when you want the switch off, you reverse polarity of the solenoid, pulling the switch up.

 

[Omar.M]

I would have to agree with everyone else saying it would be far cheaper and easier to switch the power electronicly. Anyhow, you could use a spring loaded solenoid with the shaft glued well onto the 'on' side of the rocker. When power is applied, the solenoid pushes the switch down, when power is removed, it flips is back up because it is spring loaded. This is pretty expensive, though.

EDIT: It would probably be better if you just get a non-spring loaded solenoid and when you want the switch off, you reverse polarity of the solenoid, pulling the switch up.

Yes, that was the sort of thing I was thinking of. But I guess when you're a poor-ish student, money comes before risks. I'll probably just need to pick up some relays and not stick my fingers in the wall sockets too much.

-Omar

 

[mneary]

I've found that most power strips can be opened with a little ingenuity and some pressure at the right places on the seam. Some of them have a fair amount of room inside. You may have to remove the switch (but don't remove the circuit breaker). You insert the relay contacts into the black wire (North America).

There might be room inside for a relay such as Goldmine's G1619 (99 cents). Size only 3/4" L x 9/16" W x 3/8" H.

 

[Sceadwian]

Why not just use a hobby servo? You can get them cheap and aside from a 5 volt power supply you can drive them directly from a parallel port, no complicated circuitry, you just need to write the software to send servo signals.

 

[Omar.M]

Great news. I followed Sceadwian's advice and used a servo. Had one lying around, and it did the trick. I'll get some video up soon so maybe others can see it work too, but currently, I am pulsing the servo using a PIC, and just triggering the direction changes using a button (which will be substituted for a parallel port signal later).

It seems to be working nice and dandy-- thank you very much to everyone!
-Omar

 

[Sceadwian]

The nice thing about the servo sollution is it dosen't void the warranty on the power strip if there is one. If you send no signal at all the servo only uses a small quiesient current and will last an exceptionally long time.

 

[Omar.M]

I am glad about not voiding the warranty.
The servos- as long as they last for a while, I don't mind. This room automation quest may blow over sooner or later.

For anyone who wants to see the project in working action, please check out this video I took (sorry for bad quality). It is uploaded on Youtube:
https://youtube.com/watch?v=SyHhQy-qnaU

Thank you all once again,
-Omar

 

[kchriste]

I'm impressed. That's amazingly fast and efficient.

 

[Super_voip]

So to avoid warranty issues with a $20 power strip, how much was the solution? And what woul;d the cost be to control every swith on the power strip cost?

 

[Sceadwian]

He said he had a servo laying around, so it didn't cost him anything.

 

[Omar.M]

Well. I didn't want to mess with mains. That was the big part. So long as I found a solution that lets me turn it on and off (power strip) without messing with mains-- I'm happy!

I had all of the parts lying around. So it cost me nothing. Really, since I'm going to be picking up a junk power strip anyways (will cost about a buck or two)-- it'll be for lights and I don't need it to really protect anything.

But to be fair, one can pick up a servo for about 4-5 bucks, and I've heard that the dollar store carries power strips (not good ones, but for light and possibly fan, it should do) so we're talking about 6 dollars per strip.

I don't think I'll be controlling much else in my room. There's nothing else to control.

 

[Hank Fletcher]

Great video, but I'm not too sure about the soundtrack. Sharpening the fourth degree of just about any mode can sound pretty hip, but that female singer is way off pitch - just compare her two pas. Maybe there's a convention of that music that I'm missing, but I don't think so.

 

[Omar.M]

Hanky-Poo. You... you... devil .
Just kidding. You are a funny man.

Actually, when I took that video, some cheesy Bollywood movie was running on OMNI1. Bite me .
-Omar
Edit: And I presume that they were lip syncing a song.