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Question about "turning on computer" without a case.

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Is the timer counting down, like do you hear the relay turn on and off a little bit after? I would think the output of the 555 should be going to the coil though... but it may not be able to drive it so may need to use a transistor.

The idea is you want the main power switch to power the PSU and the 555 timer circuit (via the standby power pin) but the relay should only turn on after a few seconds and then turn off, to temporarily cross the pwr switch pin on the motherboard. Enough time to simulate power switch press.
 
Ok now try replacing the +5V wires going to coil with clock pin 3.

Was supposed to be two tests, didn't explain well.

I am blaming it on pvc cement :awe:
IMG_20200613_153320.jpg
 
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Red Squirrel said:
Is the timer counting down, like do you hear the relay turn on and off a little bit after? I would think the output of the 555 should be going to the coil though... but it may not be able to drive it so may need to use a transistor.

The idea is you want the main power switch to power the PSU and the 555 timer circuit (via the standby power pin) but the relay should only turn on after a few seconds and then turn off, to temporarily cross the pwr switch pin on the motherboard. Enough time to simulate power switch press.
Click to expand...
I don't have the timer hooked at all to the relay i was just doing it as he mentioned to test out the relay to see if it works with +5V I think.

sdifox said:
Ok now try replacing the +5V wires going to coil with clock pin 3.

Was supposed to be two tests, didn't explain well.

I am blaming it on pvc cement :awe:
View attachment 23048
Click to expand...
LOL.

Okay now I'm a little confused again since I don't have anything hooked to the timer right now just to the relay, I didn't do anything like through the timer to the relay.

So now you're saying to just put the timer into the mix and hook the timer into it?

Do you mean to basically get everything back to how it was here:

555-timer-delay-before-turn-off-breadboard-circuit.png


And setup the relay how I had it in my test above, but instead of +5v from ATXPSU going to the relay, make the pin3 from the timer go to that spot in the relay?

You also said +5 wires (plural) from relay to pin3 but there is only 1 +5v wire on the relay so was a bit confused by that.
 
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purbeast0 said:
I don't have the timer hooked at all to the relay i was just doing it as he mentioned to test out the relay to see if it works with +5V I think.


LOL.

Okay now I'm a little confused again since I don't have anything hooked to the timer right now just to the relay, I didn't do anything like through the timer to the relay.

So now you're saying to just put the timer into the mix and hook the timer into it?

Do you mean to basically get everything back to how it was here:

555-timer-delay-before-turn-off-breadboard-circuit.png


And setup the relay how I had it in my test above, but instead of +5v from ATXPSU going to the relay, make the pin3 from the timer go to that spot in the relay?

You also said +5 wires (plural) from relay to pin3 but there is only 1 +5v wire on the relay so was a bit confused by that.
Click to expand...


Yeah singular +5v that was going to the coil should now be replaced with pin 3 output of the clock.
And I mean the original delay off circuit not involving PWRPIN. So yeah back to that picture.
 
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Damnit I just realized that I had the NO and NC pins swapped around yesterday. I had the PWRPin to NC and Ground to NO.

When I put them the right way which is PWRPin to NO and Ground to NC, the LED never turns on.

If I have them the wrong way as I did yesterday, the light always stays on as soon as it's connected to the motherboard as long as it's in standby mode and the PSU switch is turned on.
 
purbeast0 said:
Damnit I just realized that I had the NO and NC pins swapped around yesterday. I had the PWRPin to NC and Ground to NO.

When I put them the right way which is PWRPin to NO and Ground to NC, the LED never turns on.

If I have them the wrong way as I did yesterday, the light always stays on as soon as it's connected to the motherboard as long as it's in standby mode and the PSU switch is turned on.
Click to expand...

It's ok just wanted to see if your relay works with 5v
 
sdifox said:
It's ok just wanted to see if your relay works with 5v
Click to expand...
So does that mean it does work? Should I still try out what you were saying?

I had assumed that the light would turn on when powered on and off when powered off if it was working - was that a wrong assumption?

Also the way it's powering on the ATX PSU, it's just taking the +5v and ground from the JAMMA interface board when that game is selected, so I am assuming that means it does work with +5v?
 
purbeast0 said:
So does that mean it does work? Should I still try out what you were saying?

I had assumed that the light would turn on when powered on and off when powered off if it was working - was that a wrong assumption?

Also the way it's powering on the ATX PSU, it's just taking the +5v and ground from the JAMMA interface board when that game is selected, so I am assuming that means it does work with +5v?
Click to expand...
Look like the relay works with 5v.
 
sdifox said:
Was resistor + led on common?

Did you hear the relay click on?
Click to expand...
Resistor + led was on common with the ground of the LED going to the GNDPin.

I didn't hear any click but I also wasn't looking for it and it's kind of hard to hear since the fans and stuff turn on on the PSU right there. I can listen for it though.
 
purbeast0 said:
Resistor + led was on common with the ground of the LED going to the GNDPin.

I didn't hear any click but I also wasn't looking for it and it's kind of hard to hear since the fans and stuff turn on on the PSU right there. I can listen for it though.
Click to expand...

which way was it that it lit up? was the pwrpin on NO or NC?
 
sdifox said:
which way was it that it lit up? was the pwrpin on NO or NC?
Click to expand...
It was lit up when I put PWRPin to NC by accident. I thought it was on NO until I realized it this morning that I had NC and NO backwards. And it lights up as soon as I flip the switch on the ATX PSU even when it's in standby.
 
So I'm pretty sure I do not hear any clicking at all on the relay. I am pretty sure that I can hear the clicking of the other relay that is turning on the PSU though, and I kept my finger to the side of it and I can also feel it when it clicks too. I'm not getting anything like that with this relay though when trying it out.
 
Fuck me I just realized that the other relay I am using has +12v going to the coil and not +5v like I had mentioned and thought. So I'm guessing that +5v just isn't enough to trip the relay. I have been looking at this thing for like the past hour trying to figure out WTF is wrong and why won't it work, but now it makes sense. I could in theory run a wire from the +12v on the HDD connector though for the relay.
 
sdifox said:
So it's a 12v relay, although the spec sheet mentioned a whole bunch of voltages.
Click to expand...
Yeah I guess so. It does work fine with 12v but then I went back and saw you said to try and hookup the PWRPin to it, and then realized you said to replace the 5v that fed the relay with the PWRPin, which obviously won't work since it's not 12v.
 
Looking at step 3 of this here:

www.instructables.com

555 Timer

555 Timer: This tutorial provides sample circuits to set up a 555 timer in monostable, astable, and bistable modes as well as an in depth discussion of how the 555 timer works and how to choose components to use with it. The 555 timer is a chip that can be us…
www.instructables.com www.instructables.com

It looks like it is saying the timer doesn't really "connect the two pins" for the duration, but more that it pulses out voltage for the duration.

Could this explain why it's not jumping the pins even though it's lighting up the LED?
 
purbeast0 said:
Looking at step 3 of this here:

www.instructables.com

555 Timer

555 Timer: This tutorial provides sample circuits to set up a 555 timer in monostable, astable, and bistable modes as well as an in depth discussion of how the 555 timer works and how to choose components to use with it. The 555 timer is a chip that can be us…
www.instructables.com www.instructables.com

It looks like it is saying the timer doesn't really "connect the two pins" for the duration, but more that it pulses out voltage for the duration.

Could this explain why it's not jumping the pins even though it's lighting up the LED?
Click to expand...
Pretty sure we are using it in monostable mode. Pulse as in one continuous signal for x seconds, not flipping on and off x times.

Do you have a link ti the clock datasheet?
 
sdifox said:
Pretty sure we are using it in monostable mode. Pulse as in one continuous signal for x seconds, not flipping on and off x times.

Do you have a link ti the clock datasheet?
Click to expand...

What would you expect the readings from the multimeter between the input +5V and pin3 with the circuit here:

555-timer-delay-before-turn-off-breadboard-circuit.png


Because the readings I get isn't what I would expect, just based off of the light turning on/off. I would expect it to be +5v while the light is on and nothing once the light turns off. But I am not getting that and that is making me wonder if it's just not doing what I thought it would, but then again, I know nothing about this stuff lol.
 
I was also just looking around and saw this on youtube and it's quite different than the one we have tried thus far, like as far as the way it's built and everything, using a 555 timer.

 
purbeast0 said:
I was also just looking around and saw this on youtube and it's quite different than the one we have tried thus far, like as far as the way it's built and everything, using a 555 timer.

Click to expand...

Well the switch was used to send the pulse to start the timer, the version you built starts time when the circuit get power.
 
sdifox said:
Well the switch was used to send the pulse to start the timer, the version you built starts time when the circuit get power.
Click to expand...
Wouldn't it be the same though as that one in the video, except of pushing the button, it would just turn on if power was sent to pin2?
 
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