Computer Keep On Circuit

Brownout

Joined Jan 10, 2012
2,390
but it also means i need to put it on a circuit board or piece of breadboard or something larger like that, not just solder the leads together
Circuit boards can be made quite small. Much smaller than trying to build something out of discreete components.
 

mkbutan

Joined Sep 30, 2008
299
Here is how I might do it.

When there is no power on the USB port the timer will start oscillating. 1 second on / 10 seconds off.



Power supply is from a wall wart. Exact voltage dictated by the relay K1 coil. Call it 5VDC to 15VDC.

You could build this simpler, but be careful. I don't see a way of doing this without some time delay somewhere.

You might be able to get by with the relay "pressing" the on switch if the USB port is down.





sorry bill it was an human error i write'd in reciprocal manner 3 sec is for turning off

but pl explane
in your ckt. I/P from USB as the USB have 4 pins i.e. 1>.+5V; 2>.D+; 3>.D-; and 4>.Gnd.
from the 4 pins which is the I/P to the Ckt.
is it +5v if I am not wrong ?
 
Last edited:

mkbutan

Joined Sep 30, 2008
299
hi,
what is the use of the server to you,
are you saving any data on it / its doing any financial transaction (Sale/Purchase)
or for the backup ?
continuasly shutting down and restating the PC/server will destroy your HDD and RAM even it can destroy your MOTHER BOARD and the CPU ;even if you put any timer ckt. (with NE555/CD4060 ) or even replacing your main's socket switch normal with the 2 way switch (as even any one closes from the mains switch it will be in ON state)
 

Wendy

Joined Mar 24, 2008
23,415
Usually pushing the on switch for one second will start the computer, the rest is boot up.

With the parents in the room I'm thinking a 3 minute delay is probably better.
 

Ctenom

Joined Nov 1, 2010
59
Just diconect the power button header from the motherbored and activate a lock screen. if you run windows server this is default anyway when you have to press Ctrl Alt DEL to login. however it could still me turned off at the wall
 

BSomer

Joined Dec 28, 2011
434
Just diconect the power button header from the motherbored and activate a lock screen. if you run windows server this is default anyway when you have to press Ctrl Alt DEL to login. however it could still me turned off at the wall

Then remove all plugs and "hard wire" it to the wires in the outlet box in the wall.

problem solved :D
 

Thread Starter

Kool1zero

Joined Feb 13, 2012
24
Circuit boards can be made quite small. Much smaller than trying to build something out of discreete components.
maybe in a industrial or commercial setting. But when im making one maybe two its more of a pain to make it smallest
hi,
what is the use of the server to you,
are you saving any data on it / its doing any financial transaction (Sale/Purchase)
or for the backup ?
continuasly shutting down and restating the PC/server will destroy your HDD and RAM even it can destroy your MOTHER BOARD and the CPU ;even if you put any timer ckt. (with NE555/CD4060 ) or even replacing your main's socket switch normal with the 2 way switch (as even any one closes from the mains switch it will be in ON state)
Well, the problem is mostly shoddy power and less parents. Our power will flicker for 10-15 secs or just shut off and return back a few minutes later. The circuit will make sure it comes right back on when it can.

Just diconect the power button header from the motherbored and activate a lock screen. if you run windows server this is default anyway when you have to press Ctrl Alt DEL to login. however it could still me turned off at the wall
Very inventive solution...this with a black screensaver and the circuit completely solves the problem. All I have to do is put a disable somewhere out of sight/ hidden
 

mkbutan

Joined Sep 30, 2008
299
take the online UPS (it have in built Battery) normally for 15 Mint.
and in BIOS setting change it to 'switch on' "on" power restore option or on the "wake up on LAN" option
 

Brownout

Joined Jan 10, 2012
2,390
Kool1zero said:
maybe in a industrial or commercial setting. But when im making one maybe two its more of a pain to make it smallest
It's the easiest and best way to make one or two. You can get proto boards that simplify the process. It's much easier than just trying to soldier a bunch of leads together or trying to build timers from discreete components, which is sure to end in disaster, and can be made much smaller. Take it form someone who has done this for 30 years. I know what I'm talking about.
 

Wendy

Joined Mar 24, 2008
23,415
Agreed. This goes back to the experience level question. I was etching and making breadboards in my teens. Rats nests tend to work poorly if at all, and do you want to do this to your computer if it goes wrong? The fact is a neatly laid out board is much smaller than the alternative.

Small footprints bread boarding are not large, and the typical PC case has lots of spare room.
 

Thread Starter

Kool1zero

Joined Feb 13, 2012
24
Well, I was thinking that a relay with a normally closed relay contact and just keep the relay energized. Powered from a +12v for a drive or something for a cheaper relay. Way smaller and simpler. But thats only if I'm understanding this right. I'll try and tried a diagram later tonight. Toss in a couple caps in parrallel to make it charge up slower
 

Brownout

Joined Jan 10, 2012
2,390
To get any appreciable time delay, the capacitors will be astronimical and ginormous in size. Unless you've changed your mind about the amount of time to delay, you'll need a real timer.
 

mkbutan

Joined Sep 30, 2008
299
hi
do you mind trying this ? but on your own risk !!!!!
by the way tel me one thing after the restart of your PC/SERVER don't you have to start your application (may be SQL Server).
 

Attachments

Thread Starter

Kool1zero

Joined Feb 13, 2012
24
that's a fair point, i hadn't worked the math out then, but i see your point on the. for example if i used a 100μF cap and a 75KΩ resistor then that would be a τ of 7.5s right? about 4 time constants to charge fully would be 30s. even if the relay coil pulled the switch at 3/4 of its labeled value then you would see it at like 20 seconds on the low end.

right? or am i doing my math wrong?

by the way tel me one thing after the restart of your PC/SERVER don't you have to start your application (may be SQL Server).
that's easily enough covered with a batch in the startup folder.
mines running mainly file, but i also like to dabble in programming and i'm trying to write some software that will log some stuff and i want it to log back to my home computer when it can. (i may end up using SQL to add/update entries too)
 

Audioguru

Joined Dec 20, 2007
11,248
Why don't you ask your electrical utility company to fix its distribution so it doesn't have frequent power outages?

My electricity was designed to be reliable. It hasn't even blinked for a moment for years.
Except it turned off 2 years ago for a couple of seconds when they changed my old meter to a Smart Meter. Also a few years ago it blinked during a thunder storm.
 

Brownout

Joined Jan 10, 2012
2,390
Kool1zero said:
right? or am i doing my math wrong?
It doesn't really matter if your math is right or wrong, what matters is getting a circuit that will work. What is going to drive your realy. All the calculations in the world are irrelevant uless you've thought about the circuit details.
 
Top