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Body Count

join:2010-09-11
Columbus, OH

EMI Shielding 220 volt stove line over a data rack

First of all here is a picture of where I need to mount a 7u wall mount rack. It's either here or next to my hot water heater which I really don't want to do. If my water heater springs a leak, it's over for my electronics in the rack. Only other place would be drill into brick which I don't want to do.

That being said, the power line on top in the picture is my stove 220 volt line. The pipe on the left is a gas line which isn't even used. The two vertical 2x4's fit the mounting plate of the 7u rack perfectly. I won't be able to get it one foot away from the 220v line. So EMI shielding needs to be installed.

Copper mesh sheets costs way too much for my budget. A 1'x1' square I found for $10 and by the looks of it I'll need at least 10 squares.

I was thinking of buying thin copper wire, like what you get at a hobby store for arts and crafts. Then hammering in small nails on the beams above trying to get as close as I can together. Finally I would use the wire in a criss cross pattern back and forth and take the end of the wire to a grounding source.

Would this be enough to filter out the EMI interference? Whats going in the rack is one 24 port cat5e panel (non-shielded) and one coax patch panel (non-shielded). Using non-shielded cat5e data cable. Also using quad shielded coax. Bottom section of the rack will have a shelf with my cable box and free standing gigabit switch.

I tried to find a copper braid cover that I could maybe place directly over the 220v line but couldn't find one big enough for 8 gauge wire.


mattmag
Premium,ExMod 2000-03
join:2000-04-09
NW Illinois
kudos:3


I'm far from a networking expert, but I really doubt you'll have any issues at all with EMI off that circuit.

Speedy Petey

join:2008-01-19
reply to Body Count
I also HIGHLY doubt you'll have any interference problems at all.
Besides, that is SEU cable. The neutral is concentric and surrounds the hot conductors. Almost like a shielded cable.

Body Count

join:2010-09-11
Columbus, OH
reply to Body Count
This line was installed when the house was build which was 1967. I doubt it has any EMI coating built into the outer layer of the casing.

I can see maybe a 110v line not having issues but this is a 40 amp 220v line that powers my stove. 8 gauge wire. I don't want my network to crash whenever my wife cooks me dinner lol.

Body Count

join:2010-09-11
Columbus, OH
reply to Body Count
Click for full size
Here's the cable markings. From this can you tell if it's shielded already?

robbin
Premium,MVM
join:2000-09-21
Leander, TX
kudos:1
reply to Body Count
said by Body Count:

This line was installed when the house was build which was 1967. I doubt it has any EMI coating built into the outer layer of the casing.

The cable may not have been designed with EMI protection in mind, but if it is SEU cable then it's design serves about the same thing. As Speedy Petey See Profile stated

said by Speedy Petey:

Besides, that is SEU cable. The neutral is concentric and surrounds the hot conductors. Almost like a shielded cable.


Body Count

join:2010-09-11
Columbus, OH
reply to Body Count
Type SE is the same as Type SEU? Service Entrance Cable. Google doesn't really say if they are the same type of cable.


billaustin
they call me Mr. Bill
Premium,MVM
join:2001-10-13
North Las Vegas, NV
kudos:5
reply to Body Count
The 'twisting' of UTP cable is designed to help resist interference from outside sources. I don't think you will have any problems.

I have a similar circuit in non-metallic conduit running parallel with my main Cat5e cable for about 80 feet with less than 1 foot of separation. I have no performance issues.

If you really want to shield the cable, pull the circuit and run it inside metal conduit. Make sure that your panel is properly grounded, and the conduit has a proper ground connection to the panel. That should provide adequate shielding, and should be less expensive than the other options you have explored.


ArthurS
Watch Those Blinking Lights
Premium
join:2000-10-28
Hamilton, ON
reply to Body Count
Doubt you will have problems here, but if you want to play it safe, put some cheap iron plates above the rack, ferrous metals work better.

Body Count

join:2010-09-11
Columbus, OH
reply to Body Count
Thanks for the answers. I was planning on grounding the entire rack. Also since I'm running quad shield coax, I was planning on mounting the coax patch panel on top then the cat5e panel under it (under a 1u wire management panel) to give the unshielded cat5e a little more space from the 40amp line. I'm not too worried about the quad shield coax. I figure 4 layers of shielding should filter out most of the EMI already.


nunya
LXI 483
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12

4 recommendations

reply to Body Count
You're making a mountain out of a grain of sand.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS
reply to Body Count
Complete non-issue. If you were running WiFi from that location there MIGHT be a TINY bit of interference, but most if your problems would most likely stem from dimmer switches and CFLs. For wired networks there is very little you can do to cause interference with them when properly grounded and within tolerance of specifications.

Body Count

join:2010-09-11
Columbus, OH
reply to Body Count
I was planning on adding a plug in light socket near the rack for extra light when working on it. Was either going CFL or LED. Looks like I'll choose LED.


dennismurphy
Put me on hold? I'll put YOU on hold
Premium
join:2002-11-19
Parsippany, NJ
kudos:3
Reviews:
·Verizon FiOS
reply to nunya
said by nunya:

You're making a mountain out of a grain of sand.

Absolutely. How much telco gear have I seen inches from some nasty, unshielded, antique rectifiers?

Too much to worry about a 240v circuit in a residential home.

patcat88

join:2002-04-05
Jamaica, NY
kudos:1
reply to nunya
said by nunya:

You're making a mountain out of a grain of sand.

Unless you (OP) have the equipment to test for EFI/EMI, and an resonable target value to reach, you have no reason to care. Are you also going to run your IT equipment on isolation transformers and isolated ground (on the long list of junk IT FOD) outlets? Use STP instead of UTP?

»www.aes.org/sections/pnw/pnwreca···nw05.pdf

Stick a clamping amp meter on your coax. If it is 0.00, never think of it again. IT equipment is bonded to regular ground wire/armored cable jacket. Bond all metal things together.

Another hint, read about how an ethernet card (I didn't say cable) is wired. You will find out inducted AC current means nothing at all on ethernet. On the other hand, if a non-CFL fluorescent bulb starts to glow if you touch one of the pins in your house, THEN it is time to get serious about interference


Raphion

join:2000-10-14
Samsara

1 recommendation

reply to Body Count
Resistive loads, like that stove, are the quietest kind of load you can find.

I'd spend less time worrying about EMI, and more time worrying about the aluminum wiring in your house.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
reply to nunya
said by nunya:

You're making a mountain out of a grain of sand.

+1

TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel
reply to nunya
said by nunya:

You're making a mountain out of a grain of sand.

Completely agree.

Stove power cable is the least of your worries as far as EMI/RFI is concerned.

Also, at my work, we have network equipment installed in some environments where there is a lot of RF, using standard UTP cable, and it has never been a problem.

Network gear is quite resistant to EMI/RFI. Unlikely you'll ever run into a problem in a residential situation unless you did something like running AC and ethernet together in the walls without any separation. Even then, may or may not run into problems.

itguy05

join:2005-06-17
Carlisle, PA
reply to nunya
said by nunya:

You're making a mountain out of a grain of sand.

+3. Don't worry about it.

I work in a data center and we've had networking cables run near 220 and 440 without issue for years. Never any issues and never any performance issues. We've since moved to separate them but it's more because the raised floor was getting too crowded and impeding airflow not for problems with performance.

kherr
Premium
join:2000-09-04
Collinsville, IL
Reviews:
·Charter
reply to Body Count
I have all of my switches sitting right next to the power panel and not had any issues. Also, before I knew what I was doing, I ran a cat5 feed to my detached garage "around" the pvc conduit in the basement of the 100 amp service. The conduit in the ground is laying right next to conduit with 3-way switch legs. I also broke a big no-no by using 2-66 punch blocks. No issues. I get full rated speeds + of the NAS that's out there.


Gordo74
Premium
join:2003-10-28
Monroeville, PA
reply to Body Count
said by Body Count:

I was planning on adding a plug in light socket near the rack for extra light when working on it. Was either going CFL or LED. Looks like I'll choose LED.

You'd be wrong there if you're concerned about interference... however, your network will be fine no matter what is going on around it.

»www.youtube.com/watch?feature=pl···MhjXcmoA

Body Count

join:2010-09-11
Columbus, OH
reply to Body Count
Looks like the only EMI free energy savings light bulb would be a halogen.


billaustin
they call me Mr. Bill
Premium,MVM
join:2001-10-13
North Las Vegas, NV
kudos:5
You're worrying way too much about this. Just put in a CFL or a fluorescent fixture. It won't be on 24 hours a day. It won't emit enough EMI, when it is on, to cause a problem.

AVonGauss
Premium
join:2007-11-01
Boynton Beach, FL
reply to Body Count
said by Body Count:

Looks like the only EMI free energy savings light bulb would be a halogen.

Not to pile on, but you are definitely over thinking this one. You'll probably get more "interference" from the internals of the electronics that you're going to put in the cabinet than you will get from the electrical line or any surrounding lighting combined. Just follow the common rule of not running data lines directly parallel and next to the electrical and you'll be fine.


old_tech
Premium
join:2013-03-31
Springfield, IL
reply to Body Count
What gives you the idea that you have so much EMI when your electric stove is running, that you need to create some type of Faraday cage to protect consumer grade electronics.

My whole network setup, is within one foot of my main power panel, with the run of about six Cat-5e running up along next to it, then crossing over about twelve romex lines. Never an issue with EMI with that setup, in over ten years.


old_tech
Premium
join:2013-03-31
Springfield, IL
reply to Body Count
said by Body Count:

This line was installed when the house was build which was 1967. I doubt it has any EMI coating built into the outer layer of the casing.

I can see maybe a 110v line not having issues but this is a 40 amp 220v line that powers my stove. 8 gauge wire. I don't want my network to crash whenever my wife cooks me dinner lol.

Again, never going to happen. Really you need to study this stuff a little more, because it will never happen. Walk into any Central Office or NOC, and you will see hundreds of miles of 240v 40 & 60 amp electric wiring running all over the place.

I would be concerned, if you were running the network gear inside a electrical vault with thousands of volts and hundreds of amps in it, but you are talking 240vAC, 40 amps at the most for that stove.

It is not going to be a issue, unless you take all the jackets off of your Ethernet wiring, and flatten out the twisted strands, laying them wrapped around old Romex or SEU.


old_tech
Premium
join:2013-03-31
Springfield, IL
reply to Body Count
said by Body Count:

Thanks for the answers. I was planning on grounding the entire rack. Also since I'm running quad shield coax, I was planning on mounting the coax patch panel on top then the cat5e panel under it (under a 1u wire management panel) to give the unshielded cat5e a little more space from the 40amp line. I'm not too worried about the quad shield coax. I figure 4 layers of shielding should filter out most of the EMI already.

Again overkill. You do not need to ground the entire rack, nor do you need Quad shield coax.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to Body Count
said by Body Count:

Looks like the only EMI free energy savings light bulb would be a halogen.

I am a ham radio operator and my house is full of CFLs and LEDs. No issues at all.

Halogens waste valuable watts which are especially important when running on emergency power.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to old_tech
said by old_tech:

Again overkill. You do not need to ground the entire rack,

If there is anything electrical in that rack UPS server etc. then it should be grounded.

Body Count

join:2010-09-11
Columbus, OH
reply to Body Count
I forgot to mention that my backyard has one of those big electrical transmission towers. The big kinds you see out in the country that supply electricity from the power plant to a big city. My house is roughly 300-500 feet away from the actual wires.

It looks exactly like this:

»upload.wikimedia.org/wikipedia/c···n_ds.jpg

but only about half the size. I'm guessing it's carrying 345 kV electricity but it could be one that's carrying 765 kV. My electric company won't tell me exactly after asking several times over the phone.

This is why I did quad shield coax. Just in case. Quad shield coax was cheap to begin with. I got 100 foot rolls for $6.00 brand new.

I know there were several tests done in the 20th century about these towers and causing cancer and that they've been found to be false. I just hope my 3 year old son doesn't one day try to climb the tower haha. It's got barb wire about 20 feet up so you can't climb it.

It's fun when it rains. I can hear the crackle of the current going through the lines.