Relay Controlled Backup Hard Drive

Use a $3 relay to turn your External Hard Drive ON and OFF Automatically !! The hard drive enclosure below is a "Vantec USB 2.0", and it houses a 500 GB Seagate drive - suweeet !! I have two of them and they are critical !! They have saved my butt on more than opne occasion. But I got sick of constantly turning them OFF and ON !! I also often forgot to turn them OFF along with my PC, and they would spin all night. I even forgot to turn them ON when I booted the PC, and would then have to do a full reboot !! Here we FIX all of that with a cheap relay.

The Backup Drive has saved many a career. Once you have one you can't imagine ever living without it. But there is one BIG problem - they do not turn ON and OFF along with your PC. So they spin incessantly, even while your machine is off.

But with a relay, You won't ever forget again, because YOU don't have to do it anymore !!

The same relay can also be used to control an Auxiliary Power Supply. The aux supply is not needed by most - but it is a Godsend for Power Users and for anyone heavily into Case Modding. The external supply drives all those fancy things and leaves your main PSU alone to do its job. Again we have the same problem - the aux supply does not shut off with the PC !! The fix, once again is the Relay.

I have 3 devices: 2 drives and one aux PSU. I used to have to reach behind and shut each one OFF - every time I turned OFF the PC, and every time I turned ON the PC. It was always a hassle and I'm glad it over and done with.

Step 1 Sample system that needs Aux Power

Here is my own system called The Bubbler (click for my site's detailed Description of this machine) - which will be a "Mega-Instructable" at a later date. this might give you an idea how somebody might need both a Backup Drive AND auxiliary power. As you can see, I have a ton of added lighting components, so I run one auxiliary supply to take the load off the main PSU. Both drives and aux PSU run off the relay - and I haven't touched a switch since !!

Comments

[vov35]

did you just take 11 steps to explain how to connect four wires to a relay..........

[agis68]

The Xmas tree syndrom hits again!!!....all the voltage goes to charge the gismos and no power for the VGA.....nice.....Here in Greece we do this in big 18whell trucks.Anyway just kidding!. Nice job ...but I am afraid really these backup units for power loss...and loss of data.

[richms]

There are powerstrips that do this already for a lot more money so its a proven idea that is known to work. They use power sensing of the PC being on to liven the other outlets on it and cost 10 times what this would to make. I would rather get a 5v solid state relay and power it from a USB port so the whole thing is external to the case. I would expect that machine gets taken places quite often since its quite a showman ;)

[Solderguy]

Some external hard drives like the Western Digital My Book Series drives turn themselves off after you turn your computer off, put it in sleep mode or after 5 minutes. I got the 1 terabyte drive from Wal-mart.

[NT86]

its las vegas in a box XDD

[Metalron]

it may cause head crash upon sudden stopping!!

[trebornotca]

I used a relay wired to the 12V supply to turn off the 110V speaker amp with the PC. You are right about the downfall of external drives! It is too bad Vantec didn't think to wire in a relay off the 5V USB feed to cut power when the PC shuts down. You won't have a backup drive for long if it is left running for days or weeks at a time. I have come up with a different idea. I currently have 5 external drives. I wired a bank of 6 DPST switches to make a power switching harness into a drive bay, cut off the AC adapters and soldered on the 4 pin PC power plugs to all the external drive power cables. Now the USB drives all get their power from PC power supply. The wire colours inside the Vantec power cable are (confidently) red-5V and yellow-12V.(black & grounds are interchangeable) You just need the sense to not have all 5 0r 6 drive turned on at once. Like any USB devices, the drives can be turned on and off with the PC in use. I soldered a plug on one of the AC adapters as well so if I ever need to use an external drive as a portable I still can.

[maker12]

you put a flyback in the computer to power the plasma bulb~lol!

[lemonie]

Crikey! It's like Las Vegas. What are the advantages (to you) of having external hard storage over putting it inside? L

[Myself]

If it's not spinning, it can't be destroyed by malware or a brain-damaged kernel on a filesystem-corrupting rampage. If it's on a different power supply, it won't be roasted when a bad PWM driver and faulty crowbar circuit conspire to send 170v (the p-p voltage of 120v RMS) to all the components in the box. If it's outside the box, it's easy to detatch and swap with its mate which lives off-site, so last week's backup is in a safe-deposit box somewhere. If it's external, it doesn't contribute to the cooling fans' burden.

[GoatBoy]

I've read most of your reasoning, and most of it makes no sense. I use a simpler approach on one of my machines. Use a power strip and a decent OS that has a log/journal filesystem. Time to turn everything off? Hit the switch on the power strip. Done. $0. If you're really fancy, you set the BIOS to auto-power-on so you really do only have to press the one switch on the power strip. Unless you were able to control that relay from the OS in software, this mod is purely didactic.

[Myself]

If you're usually in the same building as your computer, then this mod just saves a little labor and forgetfulness. Suppose you have backup software that can shut the computer down when it's finished running, but the external drive stays on when that happens. This mod lets you walk away or go to bed while the backup job takes place, then shuts down the drive when appropriate.

[rhkenji]

or you could use a swappable 5"25 hard drive storage (vantec has these too).. you can turn on/off the hard drive independently if you want to or you can let it run as the computer runs. it has a key too..

Im talking about something like this:
http://www.newegg.com/product/product.asp?item=N82E16817122108

[lemonie]

Yes, sounds good, and that's what i wanted to know. But I'm not sure abou the malware, after all these are connected to your machine. L

[Myself]

P.S. The first bit about "not spinning" would only apply if the drive could be started and stopped independently of the main PC. This instructable isn't appropriate for always-on PCs that want sometimes-on peripherals, but it looks like it'd be fine for folks who turn their computers off.

[cpotoso]

That is really a waste of a relay. Why not simply power the external HD enclosures directly from the PC power supply? It provides high quality 12V (and 5V too) and only when the PC is on. I have done it on numerous occasions when I got tired of having those ugly black bricks hanging around. This is a much better, cleaner and energy efficient solution.

[PCdoc]

It's not a waste, messy or ugly either. I added one small black box that is behind and out of view that runs 3 items for me. The two drives use no power from my main PSU, and the extra supply gives me the added power I need. I prefer to let my main PSU run the two internal drives - and I let the wall run the outer two drives. Plus I now have 10 amps of AC that turns ON and OFF along with my PC to run anything else I want should the need arise.

[cpotoso]

Please note I am not saying that your solution is bad or anything, but I still think your relay is a waste. It is a waste because your PC power supply can generously handle the extra load with no problem whatsoever.

[westfw]

This sort of computer-driven relay is useful even without excessive mods or external drives; think of all those things that aren't useful unless your computer is on: powered USB hub, printer, monitor... The nearness of the 12V computer supply leads and the 120V AC wires in your relay box makes me nervous; I hope you at least have some sort of strain relief in the AC power wiring...

[Williz]

Your Bubbler friken scares me...

[phoenix124]

wow! very nice! excellent instructable, creative idea, and you have one freaking sweet computer! :P
you definatly belong in my group:http://www.instructables.com/group/modthis/