How much interference from 24V 400mA power through cat5e cable.

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mattbar

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My isp has this power going through the cat5 cable to power their equipment. It's 24V 400mA. That's 9.6 watts @ 24V.

The 24V 400mA power brick plugs into a power strip and connects to this tiny box that has a 4" cat cable to plug into the internet slot of the router. The other end of this tiny box has a place to plug in an ethernet cable. A cable runs from that to the plug on the wall which then continues to their equipment.

Here is what written on the cable behind the wall socket to their equipment:

BELDEN CDT NETWORKING DATATWIST(R) 5E 1594A CMR-CMX OUTDOOR 4PR24 VERIFIED (UL) CATEGORY 5E E18998 OR C(UL) CMR 2204 2405 157 0241876 FEET

The cable is much thicker. I'm guessing that it's standard 5e on the inside but the outside is much thicker to insulate it better. So this would NOT insulate any better against the 24V 400mA power running inside of it than a regular cat5e cable. If i replaced the cable between the tiny box and the wall with cat6 it should have no effect because it ultimately ends up going through a much much longer cat5e cable.

So the real question:
How will this effect my network?
 
Solution
photonboy
Okay, it's a POE device: http://www.veracityglobal.com/resources/articles-and-white-papers/poe-explained-part-1.aspx

I didn't see the point based on the explanation. Not sure why you'd have a simple AC adapter terminate with an Ethernet cable just to deliver a DC power source.

*Without knowing the entire setup, you can look at the AC ADAPTER for the maximum amperage it delivers, or the device that the cable is plugged into. Then make sure the specifications exceed this rating.
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mattbar

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I found this "CAT5 is rated at no more than 9.8 Ohms/100m"

24V @ 400mA is 60 Ohms maximum

I can't cut the cable to test the amps, and I don't have one of those things that clamps onto the wire.
 
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bill001g

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DC power will cause no interference assuming they have good filters on the power.

The standard 802.3af/at versions of PoE run 15 or 25watts of power. They run at 48v though but the current is at going to be 400ma or more.

Normal cat5e is rated to run this. The wire guage needs to be 22-24. They technically can not run thicker wire and still be certified cable.

The reason it is thicker is it is outdoor rated cable. It has much thicket coating to make it waterproof as well as UV resistant.

Mostly the difference between 24v systems is the distance the power can go. the 802.3 based PoE systems can go the full 100meters. Many of the 24volt system go less. Hard to say 24v is not a standard based solution so there is no requirement on the distance it can go.
 
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photonboy

photonboy

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???????

From your explanation, it sounds like the MODEM and ROUTER both have normal AC power and use the Ethernet cable for data transmission.

*Is there a box that ONLY connects to an Ethernet cable and does NOT have any AC wall power coming to it?

If so it might be a cable that is rated for that which means other network cables aren't suitable.

This doesn't make sense to me. Using a normal Ethernet connector but passing a lot of POWER over it? Doesn't seem likely.
 
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mattbar

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USAFRet
a cat6 cable is insulted better than a cat5 cable that is why I considered it

bill001g
Depending on the quality of the power supply 24V @ 400mA is more than safe to go through any undamaged cat5 cable because it's a mere 9.6watts. I found it online and it is a PMP/PTP POE Power Supply, so it has met some kind of standard. I have used this power brick almost non-stop for 8 years. I have no strong reason to believe anything is wrong with it other than how much it's been used. Would you expect any problems from an 8 year old constantly used power brick? About how many meters can the power go?

photonboy
here is a photo from this webpage showing what I'm talking about. I use a gateway so I have no modem.
https://swginc.net/product/cambium-pmpptp-poe-power-supply-24vdc-fixed-us-blades-acpssw-13s/
https://swginc.net/wp-content/uploads/2015/12/ACPSSW-131.jpg

jsmithepa
I didn't mean interference with data cables in proximity but rather within the same cable itself. The power from the 24V 400mA power brick runs through the same cable with all of the internet data.
 
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bill001g

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Why would you assume it is some standard. Lots of equipment manufactures design their own proprietary stuff...apple is the perfect example. This is the problem with non standard stuff there is no way to actually know without contacting the manufacture how far. The only standard for PoE are ether 802.3at or 802.3af and these are 48volt based.

 
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photonboy

photonboy

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Okay, it's a POE device: http://www.veracityglobal.com/resources/articles-and-white-papers/poe-explained-part-1.aspx

I didn't see the point based on the explanation. Not sure why you'd have a simple AC adapter terminate with an Ethernet cable just to deliver a DC power source.

*Without knowing the entire setup, you can look at the AC ADAPTER for the maximum amperage it delivers, or the device that the cable is plugged into. Then make sure the specifications exceed this rating.
 
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Solution
photonboy

photonboy

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INTERFERENCE?

There should be no loss of data bandwidth if that's the question.

Are you referring to radiated losses? Those don't exist for direct voltage. There's no interference the way I think you are asking.

If you had for example a Gigabit LAN you should get up to roughly 115MBps transmission speeds locally (i.e. copying between one SSD and another) through the network.

It's about 7MBps for an uncompressed BluRay disc.

If the INTERNET seems slow it's probably your ISP or a remote server. If it's slow locally between computers you should investigate that but there's NO REASON to believe your POE cables have the slightest thing to do with network speed.
 
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