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Saltisiak
01-18-2008, 02:16 PM
Just a thought here that could probably use some input.

I use mechanical relays to control some parts of my sequenced display (hey, it works). I have electrical boxes that I run a power cord into, that powers 2 outlets, and then a cat5 cable goes into the box as well to drive the 5vdc relay.

Since each outlet only handles 1 strand of lights (.3A), I was considering running my power and relay control through the cat5 over the 5' distance to my breakout box. For each power outlet, I'd pair the wires together (for load distribution). So in my cat5, I'd have 3 wires to hot, 3 wires to neutral, and then 1 wire for my 5vdc + and 1 wire for my 5vdc-.

Any thoughts? I know the cat5 individual wires are 22awg which is designed to handle .92A, so if I had multiple pairs, I'd be able to triple that.

Trepidati0n
01-18-2008, 02:24 PM
Depends on what kind of power. If it is DC, that is already being done here with the pixels. It is also being done with the boards that have remote SSR's as well. However, if you are talking about 110/220/etc...then the answer would have to an emphatic no on my part. The cable is not rated for that.

Saltisiak
01-18-2008, 02:30 PM
Correction on the wire guage. It's 24AWG, which is rated for .57A continuous load. 3 in parallel allows for a distribution for 1.71A. I'd have to say that the wire is well rated for this, however not directly approved for it (UL listed). I am speaking of 120VAC. I don't believe that I'm looking at any conditions that would make the setup prone to fire or even heat for that matter.

Trepidati0n
01-18-2008, 03:07 PM
I'd have to say that the wire is well rated for this, however not directly approved for it (UL listed). I am speaking of 120VAC. I don't believe that I'm looking at any conditions that would make the setup prone to fire or even heat for that matter.

I guess this is where we will have to agree to disagree.

Macrosill
01-18-2008, 05:03 PM
I strongly advise against running 110v power through cat 5.

MarkL
01-18-2008, 05:10 PM
Correction on the wire guage. It's 24AWG, which is rated for .57A continuous load. 3 in parallel allows for a distribution for 1.71A. I'd have to say that the wire is well rated for this, however not directly approved for it (UL listed). I am speaking of 120VAC. I don't believe that I'm looking at any conditions that would make the setup prone to fire or even heat for that matter.

The only way you could "safely" do this would be to put a 0.5A fuse on each conductor. That way if the current exceeded that for which the wire was rated, the fuse would blow before the wire melted. I think you'll find that the cost of all those fuses and holders would be well above using better wire.

Note that it's NOT ok to just fuse your 3 parallel strands at 1.5 or 1.7A. If one or two of the conductors were to become disconnected, you've then effectively lost adequate protection on the remaining conductor(s).

Saltisiak
01-18-2008, 05:37 PM
I think MarkL has a good point. And that's what I was looking for. We all know you can have 1000v going through a small conductor , however it's the amperage thats the concern. And the protection thats between it.

Believe it or not, the past 3 years, I've made my own version of lawn lights which is basically 1000' feet of 2 pairs of 24AWG wires with mini light bulbs spaced ever 10'. (25 pair telco cable hacked apart). It's worked very well, and I've never had an issue because I've kept well under the rating of the wire. I'd never write a how-to on that one!

The difference this time is, now I got other electronics involved which I'd look at damaging.

Indeed, there's the concern of having to fuse each of these sets. I was trying to come up with a better way of getting power out to these boxes this coming year. Right now I got 50' of 12-2 running in a ring that goes through each one of my 20 boxes, and then my network cable goes to the center of the ring for the control. Just trying to eliminate all the extras.

I'm going to upgrade the relay boxes to ssrs this year, but I still gotta keep the power distribution in mind. I'm upgrading to 48 strands this year.

Virtus
01-21-2008, 10:30 PM
I understand your thought process and I work with Power over Ethernet devices...all of it is DC. I've not encountered anything commercially available using twisted pair wire in this way. Not to say it couldn't do it (staying dramatically below the current carrying limits) but I don't think anyone (including most folks here at doityourselfchristmas) would do it themselves in the houses they sleep in.

ErnieHorning
01-29-2008, 03:10 PM
It’s not the wire itself, 24 ga can pass over an amp, it’s the insulation. Both that which is covering the individual wires and the sheath around all of them is very soft and nicks pretty easily. The insulation can easily be damaged by just stepping on it. Yeah you could fuse it, but it’s highly likely that the wire resistance would cause it to smoke before the fuse would go. It would be like filling a glass with water from a fire hydrant. You might be able to do it, but you also might not.

ppohlman
01-29-2008, 03:29 PM
It would be like filling a glass with water from a fire hydrant. You might be able to do it, but you also might not.

I love that analogy Ernie. I'll have to remember that and use it sometime.

Photovor
01-30-2008, 05:47 PM
It’s not the wire itself, 24 ga can pass over an amp, it’s the insulation. Both that which is covering the individual wires and the sheath around all of them is very soft and nicks pretty easily. The insulation can easily be damaged by just stepping on it. Yeah you could fuse it, but it’s highly likely that the wire resistance would cause it to smoke before the fuse would go. It would be like filling a glass with water from a fire hydrant. You might be able to do it, but you also might not.

I had originally considered this idea, but this is a great point, which I have forgotten. This past season I had a mole or a rabbit that had a good time chewing on a few of my ethernet cables outside. Althought my display still worked, there were a few bare places. There isn't that much insulation, and it cracks really well. Definately don't want to have to deal with all those potential shorts, nor dead critters :-).

Jeff Millard
01-30-2008, 09:27 PM
That's weird... when I first read this thread I thought about some phone wire I used for SSRs a year ago and how the mice ate through it. I didn't even make the connection to the end result until I read your post... Some electricain I am huh?

The bottom line here folks... Don't think about using a Cat 5 wire to carry the load of a string of lights. It was designed to carry RF along a network connection. We're using it to fire LEDs in a sealed opto coupler. There's no danger there. Putting 120vac on it and hooking light strings up to it is just plain foolish.

Did I ever tell you the one about the house in a nearby city, where they took an extension cord and cut off the female end? They put on another male, plugged one end into a home that had electricity and then plugged the other end into a home that didn't... It worked for a while. Right up until it got cold and someone plugged in the space heater. Both houses are gutted now...

The insulation wasn't meant to stand up to that kind of abuse. The same goes for the Cat 5. It wasn't made for AC.

Jeff

Macrosill
01-30-2008, 10:58 PM
This time I strongly, strongly advise against running 110v power through cat 5.

each time I see this topic come up again I am going to add a "strongly" to it. This way when your house burns down or someone gets hurt or worse I can not be held liable.

Photovor
01-31-2008, 10:12 AM
At least it would have all been outside :-) .

Jeff Millard
01-31-2008, 10:16 AM
Brian would say:

This time I strongly, strongly, strongly would advise against running 110v power through cat 5.

Jeff

PS I think he's pretty serious about it...

dirknerkle
04-21-2009, 05:16 PM
You can run THOUSANDS of "volts" through tiny wires, but you CANNOT run a lot of "CURRENT" (e.g. amperage) through the same wires. Think about your typical electronic camera flash gun -- lots of small wires in there and the voltage is up in the 20,000-30,000 range. Ever been "tazed?" Those little gizmos put up to 50,000 volts through a very tiny wire. Arc welders, on the other hand, operate at much lower voltage but very high amperage -- take a look at the size of a heavy-duty arc welder's cables!

.3 amps doesn't sound like much -- it's under the possible ratings of the gauge of the copper wire, but long cable runs, wire resistance, sharp bends, over-tight cable ties crunching wires together, current surges, thin insulation, plastic, dry grass or leaves, oxygen... whoa... overload that scenario and it can be like a bomb.

"Can" it be done vs "should" it be done are sometimes opposing concepts. I for one tend to follow the wire manufacturers' guidelines.

Here's a link to a page that seems to outline the current POE thinking.
http://poweroverethernet.com/articles.php?article_id=463

WireWrap
04-22-2009, 01:59 AM
You can run THOUSANDS of "volts" through tiny wires, but you CANNOT run a lot of "CURRENT" (e.g. amperage) through the same wires. Think about your typical electronic camera flash gun -- lots of small wires in there and the voltage is up in the 20,000-30,000 range. Ever been "tazed?" Those little gizmos put up to 50,000 volts through a very tiny wire. Arc welders, on the other hand, operate at much lower voltage but very high amperage -- take a look at the size of a heavy-duty arc welder's cables!
...



You also cannot safely run "thousands of volts" through tiny wires unless the insulation is designed for it.

You can think of it in terms of water systems.

Voltage is the "pressure" that forces electricity to flow. All other things being equal, the higher the voltage, the more electricity flows. This is like the water main that comes from the water company at perhaps 70 P.S.I. (Pounds per Square Inch) pressure.

Resistance is opposition to electrical flow. The more resistance (Ohms), the less electricity will pass. Think of this like a valve or faucet, or even a kink in a hose.

Current or Amperes is the actual amount of electricity that passes. The higher the voltage or the lower the resistance, the more current will flow.

For any given wire, the insulation has a high resistance to electrical flow, based on the composition and thickness of the insulation. However, if you exceed the rated voltage, current will begin to flow! Think about a hose with too much pressure -- when the limits are exceeded, the hose will split and uncontrolled flow results. Same with electricity!!! :shock: :shock: :shock:

No matter how much you want it, Cat 5 cable is not designed for significant power distribution. Each pair of wires is twisted between 50 to 65 twists per meter (different for each color) which minimizes crosstalk between the pairs, but that also makes the insulation subject to damage or cracking from stepping on the cable or pulling it too tightly around a bend - especially a kink. The more damage to the insulation, the lower its resistance. And this damage is usually hidden by the outer jacket - you can't see how bad it may be.

Stay Safe!!!

I'll beat Brian to it:
I strongly, strongly, strongly, strongly would advise against running 110v power through cat 5.

:idea:

mrpackethead
04-22-2009, 04:17 AM
I use cat 5 to power up our pixels. Its running a big fat 12V DC. We routinely supply ethernet switches for POE, that supply 48V DC to phones, at up to 15W per port. ( and the new switchs now do 30W ).

In NZ and Australia, if its below 50VDC then legally this is ok. Go higher than 50V, and youre in a whole different ball park..

Seriously the issue here is saftey.. Mains ( 110V or 230V ) voltages kill.. Cat5 cable is simply not up to the task of providing enough protection.. Just don't go there.. The insulation is'nt good enough, and also mechnically cat5 is pretty poor.. But be it on your head if you don't head the warnings of the people here... They are not talking rubbish.

wjohn
04-22-2009, 05:39 AM
DANGER Will Roberston!!!!

rstehle
04-22-2009, 11:25 AM
DANGER Will Roberston!!!!


You obviously are not old enough..........:D

As I recall, it was "Danger Will Robinson"

LOL

WireWrap
04-22-2009, 02:04 PM
From the series: "Space Family Robinson"

Wanna go back a little further? How about "Tom Corbett - Space Cadet"?

rstehle
04-22-2009, 05:00 PM
Or how about Flash Gordon..........with Dale Arden, Dr. Zarchov and Emperor Ming........ OMG, I'm old............:(

Sorry to hijack this thread..........

dirknerkle
04-22-2009, 05:13 PM
"OMG, I'm old............" ???


You're not old, you're a seasoned veteran!

I remember Buster Crabbe in those FG episodes... Those were the days!

sjwilson122
04-22-2009, 06:11 PM
I don't know about the rest of you but, I am not old.......I am 25 with 23 years of experience........

rstehle
04-22-2009, 06:34 PM
Sounds like DN and I have just a wee bit more "experience" than you.......:cool:

klanger
04-22-2009, 10:54 PM
Here's one for Wjohn, Helloooo Mr. Wilson:D


and sorry for the hijack;)

wjohn
04-22-2009, 11:19 PM
ahhhh,, I dred turning 65 and having a Dennis move in next door!!!

WWNF911
04-23-2009, 02:18 AM
Are you guys sure this thread is about power??? ;)

wjohn
04-23-2009, 02:34 AM
It stopped being about power about 7 posts ago:

Summary:

Only use CAT5 for voltages below 50VDC.

Kev Lang is still older than me.

50 and 60s TV programs are forever caught in your head.

klanger
04-23-2009, 05:26 AM
:twisted:
It stopped being about power about 7 posts ago:

Summary:

Only use CAT5 for voltages below 50VDC.

Kev Lang is still older than me.

50 and 60s TV programs are forever caught in your head.

Yes.
Yes.
and Yes

dirknerkle
04-24-2009, 04:05 PM
Back on topic...

I just completed wiring my audio feed and 12vdc through cat5 so I can move my transmitter out by the street and mount it on the back side of my mailbox. In testing, I haven't noticed any distortion or problems. With a house that's set back a ways from the street, this should enhance coverage by putting the signal out where it's supposed to be.

mrpackethead
04-24-2009, 04:33 PM
Back on topic...

I just completed wiring my audio feed and 12vdc through cat5 so I can move my transmitter out by the street and mount it on the back side of my mailbox. In testing, I haven't noticed any distortion or problems. With a house that's set back a ways from the street, this should enhance coverage by putting the signal out where it's supposed to be.

Your lucky so far. Make sure you test that with some dimmer controllers going as well. Audio on unbalanced unsheilded cable will almost certainly get some induced noise from noisy non-suprussed dimmers that are in common use.

dirknerkle
04-24-2009, 04:56 PM
Your lucky so far. Make sure you test that with some dimmer controllers going as well. Audio on unbalanced unsheilded cable will almost certainly get some induced noise from noisy non-suprussed dimmers that are in common use.

Yes. I thought of that - I have plenty of shielded microphone cable ready to go in case I get some crosstalk...

One thing I did differently was that I didn't put a low-level signal on the line, but an amplified signal and at the transmitter end, cut it back to work with the transmitter's impedance. Seems to work... no sparks at least...