Turn CPU PSU to supply PWR for CCTV?

[paparaaaapa 0]

Hi there, and i will like to know how should i do to turn it out?

I did saw some people using this method, they get a normal Power Supply with 450Watt, and then cut the yellow and black power cord and connect it back on to CCTV power adapter, which have been cut off the head from adapter. I've been wanna to try it out, but i really don't know how should i do it. Is that someone here have try this out before?

 

Thanks.

[ak357 0]

Hi there, and i will like to know how should i do to turn it out?

I did saw some people using this method, they get a normal Power Supply with 450Watt, and then cut the yellow and black power cord and connect it back on to CCTV power adapter, which have been cut off the head from adapter. I've been wanna to try it out, but i really don't know how should i do it. Is that someone here have try this out before?

 

Thanks.

 

Yes it easy

u have to short 2 pins to turn on

Pin 14 and Pin15 (Ground)

-------------------------------------------------

Edited November 9, 2009 by Guest

[Soundy 1]

ATX pinout listing is here: http://pinouts.ru/Power/atxpower_pinout.shtml

 

Note pin 14 (Green wire): "Power Supply On (active low). Short this pin to GND to switch power supply ON, disconnect from GND to switch OFF."

[rory 0]

I dont see why anyone would do this though, it makes no sense.

[paparaaaapa 0]

Note pin 14 (Green wire): "Power Supply On (active low). Short this pin to GND to switch power supply ON, disconnect from GND to switch OFF."

 

Thanks for the guide. I am thinking of using this so i don't need to use a lot of adapter for installing CCTV, say if it is 4-5s.

 

By the way, is the PSU supply is 12V? and is it compatible with the Cameras? So i will need to short Pin 14 with which Pin #?

 

Thanks Soundy.

[Soundy 1]

The blue wire would short to any of the black ones. The yellow wires will all provide 12VDC, including those on the HDD power connectors.

 

As to why... I guess "just because". I regularly see guys on various other forums asking about doing this to power their car subwoofer amps for their home theater setups, too. One thing, at least you know it's highly-regulated 12VDC. Looking at a 300W PSU I have sitting here, it says it provides up to 11A at +12VDC... that's enough to run a good number of cameras.

[rory 0]

Computer PSUs are very unreliable though, I would be concerned about noise also. For the same price or just a couple dollars more you could just buy a Fused Distributed Power Supply designed for CCTV, or even cheaper buy an Standard Altronix Power supply which is going to be alot better than the PC power supply and also cost alot less.

 

IN fact, cheaper yet is a 2amp plug in power supply you can get in the US for around $5 from any electronic store, I use one to power several cameras at my place - granted its not the best option, in fact its the same idea as you are doing now, issues with video and grounding/noise arise using that method.

 

But hey, if you have a computer PSU to waste

[Squiffy 0]

See here:

 

http://www.instructables.com/id/ATX--%3E-Lab-Bench-Power-Supply-Conversion/

 

http://www.instructables.com/id/Yet-Another-ATX--Lab-Bench-Power-Supply-Conversion/

 

Personally I find computer ATX PSUs to be much more reliable than typical individual dedicated PSUs. The latter tend to run extremely hot and are not generally well designed.

 

The ATX PSU I use to power my cameras is actually a lot quieter than my old 'lab' linear 25 amp PSU.

 

Given the ever increasing power demands for modern PCs, it's often the case that older PSUs are plentiful and available for nothing or very cheaply

[Soundy 1]

Computer PSUs are very unreliable though,

 

Only if you get a cheap junky one. The ANTEC in my PC has been working great for years. 550W, cost me about $45. Switching-mode supply, tightly regulated, up to 15A on the 12VDC rails. No, it's not the "proper" or "ideal" solution or even designed for that purpose, but there's no reason it can't work just fine.

[rory 0]

Computer PSUs are very unreliable though,

 

Only if you get a cheap junky one. The ANTEC in my PC has been working great for years. 550W, cost me about $45. Switching-mode supply, tightly regulated, up to 15A on the 12VDC rails. No, it's not the "proper" or "ideal" solution or even designed for that purpose, but there's no reason it can't work just fine.

 

Ive used some of the most expensive Antec and others and they fail regularly, but we dont have great power like Canada. I mean i have also seen a $5 power supply run for 10 years, just luck. If they want to use it thats up to them, I wont tell them its okay though.

[paparaaaapa 0]

Hi there, and i will like to know how should i do to turn it out?

I did saw some people using this method, they get a normal Power Supply with 450Watt, and then cut the yellow and black power cord and connect it back on to CCTV power adapter, which have been cut off the head from adapter. I've been wanna to try it out, but i really don't know how should i do it. Is that someone here have try this out before?

 

Thanks.

 

Yes it easy

u have to short 2 pins to turn on

Pin 14 and Pin15 (Ground)

-------------------------------------------------

 

Thanks, that's great.

[paparaaaapa 0]

Computer PSUs are very unreliable though,

 

Only if you get a cheap junky one. The ANTEC in my PC has been working great for years. 550W, cost me about $45. Switching-mode supply, tightly regulated, up to 15A on the 12VDC rails. No, it's not the "proper" or "ideal" solution or even designed for that purpose, but there's no reason it can't work just fine.

 

Yeah, some PSU is reliable, just don't took some low quality with budget limited that you ask China to make. It probably will failed you down. I am implementing the PSU with the camera, and it's seems running smooth for now.

[zmxtech 0]

right on un-reliable !

[paparaaaapa 0]

right on un-reliable !

huh? what do you mean by that?

[dvrtiger 0]

Simply shorting green and black wire is not enough for continuous operation. You also need to do following steps:

-short orange (+3.3V) and brown (sense) wires to provide feedback loop for internal stabilization and power factor correction

-10ohm/10W resistor between red (5V) and black (0V) wire

You can also add a LED indication by connecting 330ohm resistor on gray (output OK) wire in series with LED anode, and LED cathode is connected on black wire.

[paparaaaapa 0]

Simply shorting green and black wire is not enough for continuous operation. You also need to do following steps:

-short orange (+3.3V) and brown (sense) wires to provide feedback loop for internal stabilization and power factor correction

-10ohm/10W resistor between red (5V) and black (0V) wire

You can also add a LED indication by connecting 330ohm resistor on gray (output OK) wire in series with LED anode, and LED cathode is connected on black wire.

 

So basically there is 4 points i need it to be short?

[dvrtiger 0]

You have to make these steps for reliable PSU operation, if you want to turn it, and forget all about it.

Shorting black and green wire will simply start up your power supply but it will not open all 12V rails. That's why you need to short black and orange wires.

Resistor should be installed to provide full power on 12V rails without any load present on 5V rails, which is expected by ATX PSU electronics (5V level is 'master' level in this units).

[paparaaaapa 0]

You have to make these steps for reliable PSU operation, if you want to turn it, and forget all about it.

Shorting black and green wire will simply start up your power supply but it will not open all 12V rails. That's why you need to short black and orange wires.

Resistor should be installed to provide full power on 12V rails without any load present on 5V rails, which is expected by ATX PSU electronics (5V level is 'master' level in this units).

Thanks for the advices, so if i will like to open all 12V rails, then i need to follow your guide on shorting the others 2 slots? Am i right?

[dvrtiger 0]

Just bundle and solder all yellow wires together (12V) to one binding post and most of black ones to the other one, and follow my guide for the rest of the circuit (shorting green and black, resistor, etc...). Wires are just outputs, rails will be open at the transistor level.

P.S. you should use shrinking tube or isolating tape on all other unused red, orange..etc.. wires to avoid unwanted shorts and 'sudden' blackout in your house

[kensplace 0]

The method has serious drawbacks for security purposes.

 

Short the power supply on any one of the cameras, and ALL cameras powered by the PSU will go dead, as the PSU will shutdown automatically.

 

You would have to fuse every camera, and hope that the PSU didnt shut down anyway before the fuse you use blew.

 

If you didnt fuse the cameras, and their was a fault, you have to remember that these PSU's can put out some serious amperage, easily enough to set cables/cameras on fire etc if faulty and there is enough of a short to overload the psu.

 

The main problem though, is as said, kill one camera, kill them all....

[dvrtiger 0]

Fuses are mandatory We are not talking about power lines now, just how to convert it. Malfunction on any camera won't destroy them all. Switch mode power supply of flyback design, as ATX, is equipped with ultra fast switching diodes which act as fast fuses by discharging sudden spikes to the earth conductor. Think of them like they are some hybrids between diode and varistors. They use dU/dt effect for their operation. When they conduct over their upper treshold, PSU shuts down. Fuses are needed on output wires in front of every camera to prevent total shutdown in case of local malfunction on any camera.

Also, a very simple circuit could be constructed to automatically reset PSU if total shutdown is caused by external short-timer circuit based on 555 and relay.

[paparaaaapa 0]

Fuses are mandatory We are not talking about power lines now, just how to convert it. Malfunction on any camera won't destroy them all. Switch mode power supply of flyback design, as ATX, is equipped with ultra fast switching diodes which act as fast fuses by discharging sudden spikes to the earth conductor. Think of them like they are some hybrids between diode and varistors. They use dU/dt effect for their operation. When they conduct over their upper treshold, PSU shuts down. Fuses are needed on output wires in front of every camera to prevent total shutdown in case of local malfunction on any camera.

Also, a very simple circuit could be constructed to automatically reset PSU if total shutdown is caused by external short-timer circuit based on 555 and relay.

wow, it seems like i miss out a lot of the steps on switching it to provide the power for CCTV Cameras. What i did now is only connect the black and yellow power cable to provide the power for CCTV camera, i guess i gotta do some modification of that though.

[forbus 0]

right on un-reliable !

Well, I tried this on one of my systems and the system has been working perfectly fine with NO noise at all. Do I recommend? Not really. But it does work.

 

Does it work? Is it okay? Two completely different arguments.

[Squiffy 0]

For home use and with expandability in mind (if you want to progress to more than say, four cameras), I'd say it's perfectly adequate and highly cost effective.

 

I'd certainly recommend it, but only to those who understand what they're doing.

[craiga 0]

Hi.

One thing worth mentioning is that you won't really get 12.0V from this. You'll get something less, like 11.4V and the more load you place on the 12V supply the lower the voltage will be. You can get the voltage closer to 12.0V by increasing the dummy (resistor) load on the 5V supply, but you end up just generating more heat. For cameras that don't mind 11V, there's no problem, but some cameras don't behave well with anything less than 12.0V.

-Craig