Safe to wire this in? (12v DC wall warted switch)

Wolvenmoon · 03-27-2008, 01:30 PM

I just got a linksys gigabit switch to complete my upgrade to gigabit ethernet and a custom router, and saw that its power draw was 12VDC 1 amp adapted via wall wart.

Is it possible and safe/reliable to hook this up into a computer power supply, and how would I do so without killing the DC adaptor?

Thanks!

**Duke3d87** · 03-27-2008, 02:12 PM

it shouldn't matter. i think it should work

cyclonite · 03-27-2008, 03:33 PM

Buy a second adapter that will fit the router plug, cut, splice, solder on a molex connector, plug into available power source inside computer.

Not too hard

Wolvenmoon · 03-27-2008, 04:29 PM

Okay. How will I tell which to solder to the 12V and which to ground?

cyclonite · 03-27-2008, 04:38 PM

Use an ohm meter and check which lead goes to which part of the plug. Then check the device you are using for the proper polarity.

Edited for clarity

anpelley · 03-29-2008, 01:48 PM

Quote:

Buy a second adapter that will fit the router plug, cut, splice, solder on a molex connector, plug into available power source inside computer.

That, but remember that 12V 1A = 12W, so if you have the room on your PSU, maybe some other people can tell you why it's a bad idea to use your PSU. I can't. The PSU is a far better power source than a wall adapter.

furball zen · 03-31-2008, 09:53 PM

Quote:

Originally Posted by cyclonite

Use an ohm meter and check which lead goes to which part of the plug. The center is always the positive and the outer is always the negative.

Actually, its not ALWAYS that way. Some plugs have the neg on the INSIDE. Its not that common this way, but not unlikely. I dont have any of my Linksys' out where i can see them.

As far as using your PSU, your Linksys unit will only draw as much current as it needs, nothing more (assuming everything is kosher of course), the specifications on the power supply that comes with the router is because you are stepping 120VAC 60A to 12VDC 1A. Its more of a current limiter than a current source.

Im not sure about noise filtering on the PSU, if it would handle something like a router.

.....And after rereading the cryptic first post, i see you want to use the DC adapter inline with the PSU from your PC. This is not a good idea. Youre better off just plugging it in, i mean why would you want your router to be on a switched source anyways? When its off, nobody else hooked up to it will have access to the network or internet. Also i dont think they are made to have as many switched on/off cycles as a PC like if you turned it off every time you were done with the computer.

furball zen · 04-01-2008, 06:14 PM

Quote:

Originally Posted by cyclonite

It does not make any sEnSe to have the ground on the inside of the jack. I have been using them since the mid 70's and I have never came across one that has the ground on the inside.

And if some one rigged one up that way well then they are just as retarded as it sounds. You always isolate the positive side in direct currEnt. The ground or otherwise known as common side is never isolated.
Wait I remember back in 7th grade electronics class the teacher mentioning something about the French having thing ass backwards....thats it you must be thinking about one of them French things.

Dude, im not here to piss in your wheaties. If i said i've seen one, i've seen one. I may even have it laying around still....which means its a good thing to check the transformer housing (or, wart) to confirm the correct polarity.

Also, Radio Shack which used to make its living from electronics gurus and hobbyists, sells replacement adapters with (shock!) ends that you can flip around and reverse the polarity!

No offense to anyone younger here, but, im not some highschool-noob-know-it-all. I took apart (and reassembled correctly i might add) my first electronic toy at age 3, that was 30 years ago. Most of what I've learned was from my Dad who was a radar tech in the Army, 48 years ago.

Sometimes, everyone is wrong about something in their life. Its not fair to the younger (or older as it may be) generation to receive misinformation from someone who hasnt experienced EVERY possible thing in EVERY possible scenario. Maturity is the ability to say 'im sorry i was wrong', no matter what the age.

Oh, and i fixed your spelling errors. Have a nice day

furball zen · 04-01-2008, 10:43 PM

Quote:

Originally Posted by cyclonite

I do believe in my original post to the topic creator that in home network switches the adapter configuration is always the same. Could this be some level of misinformation. Could be, but until its actually proved that way. After all we are talking about home network switches.

There is a very good reason behind the isolation of the positive currEnt in networking equipment, and that is to help reduce crosstalk which leads to signal degradation.

Now OFF TOPIC

What I did is offer information that was from personal experience. And is based on something that one believe to be common sense. Which can be neither wrong nor right to some one else. You can either agree or disagree with what one person believes to be common sense.

But to insinuate that what one person believes is good common sense is wrong. Now we are talking a whole new topic here. What you end up with is a difference of opinions in which one person is trying to change the others by way of faults.

Here spell check this

So the next time you feel the need to call some one else out in an internet bulletin board chose your battle a little wiser.

LOL thats good, really good. Considering your post called me out (Mr. Big Bad Internet Man) saying i was lying (or rather, retarded) and that there was NO way you could have a reverse polarity tip on a AC to DC converter. On a CAT5 network cable (to the best of my knowledge) there is no 'positive' or 'negative' current, just transmit and receive, in a twisted configuration, not in an isolated/shielded cable ala RG8. Oh, and ive taken Government training on networking and protocols and passed with 95% or better.

Re: the OP, it looked at first read, he wanted to go to Wal-Mart and buy an adapter for his Linksys and was asking for help in selecting one. After a reread, i realized this wasnt true and answered his question, (which you seemed to miss i think), hopefully helping him in the process. Since (not sense) this is a free country and all, i can add/say what ever i want. You dont have to like it nor accept it. But, you cannot refute verifiable facts and call them a lie.

Just the same, you can NOT say that your statement is true ALL the time. Have you seen EVERY make and model of network switch or router?

Crosstalk* is noise between channels, not between a positive and negative wire/contact. The adapter cable itself isnt shielded because there is no need for it.

However, i choose to be mature about it and i digress, not because im admitting defeat, but i choose to be the better.

Oh yea, and a currAnt is a plant, not electrical currEnt......

*From en.wikipedia.org: In electronics, the term crosstalk (XT) refers to any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel. Crosstalk is usually caused by undesired capacitive, inductive, or conductive coupling from one circuit, part of a circuit, or channel, to another.

Basetballjones · 04-02-2008, 08:25 AM

Quote:

Originally Posted by furball zen

LOL thats good, really good. Considering your post called me out (Mr. Big Bad Internet Man) saying i was lying (or rather, retarded) and that there was NO way you could have a reverse polarity tip on a AC to DC converter. On a CAT5 network cable (to the best of my knowledge) there is no 'positive' or 'negative' current, just transmit and receive, in a twisted configuration, not in an isolated/shielded cable ala RG8. Oh, and ive taken Government training on networking and protocols and passed with 95% or better.

If you had taken any form of network training you would know very well that Transmit and Receive signals are actually electrical impulses.
In fact, all communications devices use electrical impulses to transfer data.
(Save radio and fiber optic- but they originate from their source as electrical impulses)

Your training; which sector of networking? Like a CCNA or NSA?

On topic- Do not hook anything that comes with a power adapter/ wall wart to your PSU. The power adapter not only transforms the AC to DC, but also maintains a safe level of current for the device- ie, it acts as a fuse/ circuit breaker.
Some adaptors also contain line conditioning rectifiers that smooth out the power signal for more efficient operation.

You could hook this stuff to a PSU, but you would need to modify things that need a few years of electrical training.

furball zen · 04-02-2008, 09:33 AM

Quote:

Originally Posted by Basetballjones

If you had taken any form of network training you would know very well that Transmit and Receive signals are actually electrical impulses.
In fact, all communications devices use electrical impulses to transfer data.
(Save radio and fiber optic- but they originate from their source as electrical impulses)

Your training; which sector of networking? Like a CCNA or NSA?

On topic- Do not hook anything that comes with a power adapter/ wall wart to your PSU. The power adapter not only transforms the AC to DC, but also maintains a safe level of current for the device- ie, it acts as a fuse/ circuit breaker.
Some adaptors also contain line conditioning rectifiers that smooth out the power signal for more efficient operation.

You could hook this stuff to a PSU, but you would need to modify things that need a few years of electrical training.

Well yea i know/knew that, i just said i wasnt sure about there being a polarity difference between positive and negative. And no, not that high, but Gov still.

anpelley · 04-02-2008, 12:42 PM

Oh, look, internet bullies!

::grabs some popcorn to enjoy the show:

Back to the topic:
In an earlier post, I said "maybe some other people can tell you why it's a bad idea to use your PSU. I can't. "
I was specifically thinking of the fact that some wall adapters don't have high quality "conditioning rectifiers" (polyphase or whatever) whereas it was my impression that a PSU gave fairly steady DC voltage. Further, I was under the impression that some DC adapters were highly susceptible to the variation in house current, and again, the PSU handles this. For those reasons, I thought it was safe to use a PSU rather than a DC adapter. If I'm incorrect in that the PSU would give a steadier 12V source than a DC adapter, please show me documentation to correct my ignorance.

furball zen · 04-02-2008, 12:57 PM

Quote:

Originally Posted by anpelley

Oh, look, internet bullies!

::grabs some popcorn to enjoy the show:

Back to the topic:
In an earlier post, I said "maybe some other people can tell you why it's a bad idea to use your PSU. I can't. "
I was specifically thinking of the fact that some wall adapters don't have high quality "conditioning rectifiers" (polyphase or whatever) whereas it was my impression that a PSU gave fairly steady DC voltage. Further, I was under the impression that some DC adapters were highly susceptible to the variation in house current, and again, the PSU handles this. For those reasons, I thought it was safe to use a PSU rather than a DC adapter. If I'm incorrect in that the PSU would give a steadier 12V source than a DC adapter, please show me documentation to correct my ignorance.

LOL bullies...

'Some' adapters condition the line, these are small enough i doubt it. Could be wrong though.

On the PSU vs Adapter output: A device whether a speaker or electronic that needs power will only draw as much current as needed to do its job.

Example, you can hook a 4ohm sub to a 500W amp, but the speaker wont draw 500W of power if the amps power output is rated at 2ohms. It will only draw 250W. So if your device draws 800mA of current, supplying it with 1A wont blow it, it will simply have a 200mA headroom as it were. However, if you supply a 1.2A draw with only 1A of power, fuses will blow and or melt down can occur.

As far as this thread is concerned, the general concensus is DONT use your PSU to power your router or switch. However, that being said, if you were to use it to power other items it 'may' be ok to do so. I think this whole site is dedicated to people who dont do things conventionally and in the box. Anything is possible. Even in a room full of idiots :)

tencent · 04-03-2008, 12:20 PM

there shouldnt be any problems doing this and using a jack to plug it in the polarity is obviously of high concern and cyclonite... they DO make wall transformers that provide the opposite polarity opposed to the standard. Use wiki and im sure its on there.

Wolvenmoon · 09-11-2008, 08:15 PM

A few months later after the flame war..

I decided not to do it. Not for any of the reasons mentioned here, but because of how our house is arranged. I thought about the power cycle argument, and since march this PC has been reset no more than three times, twice to clean it out, once to update.

Anyway, thanks for the helpful posts!