Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Ethernet cable advice for observatory

Observatory
  • Please log in to reply
33 replies to this topic

#1 wboeck

wboeck

    Mariner 2

  • *****
  • topic starter
  • Posts: 297
  • Joined: 01 Dec 2004
  • Loc: Nebraska

Posted 31 August 2021 - 03:40 PM

I am getting ready to dig my pedestal for my steel pier. I am planning on running conduit for ethernet and direct burial 12/2 electric wire in pvc conduit in a 18" deep trench and into the concrete pedestal and into the bottom of the steel pier. The observatory is 72 feet away from my house and electrical panel. I have thought about using fiber but do not want too many additional adapters and fiber to ethernet converters so I have decided to use cat 6. Does anyone have any advice for conduit? I already have 3/4" conduit for electrical but still confused on cat 6. I originally thought 3/4" but am now thinking about using 1 1/4" for a couple of lines or maybe even change to fiber something in the future. People seem to advise to use fiber for protection from lightening strikes. I have seen several people discuss installing inline ethernet ground blocks for surge protection but gives no advise on how to ground them. Seems like there needs to be a grounding rod. Other people say they have installed cat 5 or 6 without any grounding and never had a problem for years. Maybe I should install 3/4" conduit for one cat 6 cable as originally proposed and take a chance by unplugging the cable from my router when not in use. I get sufficient wifi for my security camera so I do not really need two cables. I assume I can pull new cable with the original if needed. I just want to have my mini pc  hardwired when imaging. In the past I used an extension cord for electrical and wifi. I was a pain when mowing. Thanks for any advice. 

 

Wayne 



#2 Couder

Couder

    Apollo

  • *****
  • Posts: 1,216
  • Joined: 24 Feb 2014
  • Loc: Mansfield, Missouri in the Ozarks

Posted 31 August 2021 - 04:05 PM

I went ahead and ran 220v just in case - I figured you never know. I put it in 2" PVC. I ran double CAT5 cables, in 1" PVC. Both these would fit in smaller PVC but the cost is not much more, and if I ever need to pull cables either way I have room. By the way, on the 220v  I laid the PVC out, and pulled the wire through each one, glued it, and went on to the next one. On the smaller one (cat5 is much more flexible) I glued it all together with conduit outlets on both ends where it went into the building and house. Then used a vacuum to pull a light string, which I then used to pull a nylon cord, which I used to pull the cat 5. I pulled an extra nylon cord in case I ever need to run another wire. 



#3 OldManSky

OldManSky

    Fly Me to the Moon

  • *****
  • Posts: 5,199
  • Joined: 03 Jan 2019
  • Loc: Valley Center, CA USA

Posted 31 August 2021 - 04:17 PM

I ran 100' CAT6 in 1" PVC.  Doubled up (two cables) as Couder above, one is currently unused. It's a spare.

No grounding.

No issues at all, high-speed and all good, for 1.5 years.  We just had a pretty nasty thunderstorm today...and everything was and is fine.



#4 photoracer18

photoracer18

    Skylab

  • *****
  • Posts: 4,410
  • Joined: 02 Sep 2013
  • Loc: Martinsburg, WV

Posted 31 August 2021 - 04:25 PM

I would definitely do at least 2 and maybe 3 lines of Ethernet in the pipe just in case the one you are using goes bad. Also make it Cat6 or Cat6a as it can go to 100 meters. Cat7 is only rated for 15 meters.

As for ground blocks its just like for a house, a big copper alloy rod sunk into the ground as deep as it can go. You could consider wrapping the pipe in  metal shield or mesh and grounding that.


  • OldManSky likes this

#5 EmeraldHills

EmeraldHills

    Apollo

  • *****
  • Posts: 1,455
  • Joined: 26 Nov 2006
  • Loc: Louisville, Kentucky

Posted 31 August 2021 - 04:59 PM

We're told that, at least for this city (Louisville, KY), it's against code to place ANYthing metal in the same conduit as a 110 V power line. Be sure to check your local codes. I'm guessing that there had to have been an instance of something shorting out and resulting in a fire for this to have become a code in Louisville. For this reason, our I.T. guy has concluded that only fiber can coexist in the same conduit here.



#6 kathyastro

kathyastro

    Soyuz

  • *****
  • Posts: 3,512
  • Joined: 23 Dec 2016
  • Loc: Nova Scotia

Posted 31 August 2021 - 05:08 PM

I ran 2 cat-5 cables in 1" conduit.  The 220v was in a separate 1.25" conduit.  My total cable run is about 220', but I installed a weather station part way along the trench, with the cables coming to the surface there, so my longest single pull was about 150'. 

 

I don't recommend threading the conduit sections one at a time and glueing them.  Too much chance of gluing the PVC-sheathed cable to the conduit!

 

Pulling a long run of cable is easy if:

- you use large-diameter conduit;

- any bends have a large radius;

- you start with a thin string, pulled by a shop vac duct-taped to the far end, use the string to pull a heavier cord, then use that to pull the cable

- you make liberal use of cable lube.

 

Run 2 ethernet cables.  That way you have a spare.  And pull another cord with the wires.  That way, if you have to pull another cable for some reason, you have something to pull it with.


  • EmeraldHills and OldManSky like this

#7 MJB87

MJB87

    Gemini

  • *****
  • Moderators
  • Posts: 3,067
  • Joined: 17 Feb 2014
  • Loc: Talbot County, MD & Washington, DC

Posted 31 August 2021 - 08:38 PM

My suggestion is to run 1 or more Cat6 Ethernet lines plus a string that you can use to pull through fiber down the road if needed.

 

Also, consider an Ethernet surge protector on the incoming Cat6 lines.  I just had another lightning strike on my property last week. Took out the control board for my standby generator (that's a quick $1000 down the drain) but my observatory escaped unharmed.



#8 wboeck

wboeck

    Mariner 2

  • *****
  • topic starter
  • Posts: 297
  • Joined: 01 Dec 2004
  • Loc: Nebraska

Posted 01 September 2021 - 04:50 AM

My suggestion is to run 1 or more Cat6 Ethernet lines plus a string that you can use to pull through fiber down the road if needed.

 

Also, consider an Ethernet surge protector on the incoming Cat6 lines.  I just had another lightning strike on my property last week. Took out the control board for my standby generator (that's a quick $1000 down the drain) but my observatory escaped unharmed.

What type of surge protector works and how is it installed?

 

Thanks

Wayne 


Edited by wboeck, 01 September 2021 - 04:50 AM.


#9 Brent Campbell

Brent Campbell

    Viking 1

  • *****
  • Posts: 990
  • Joined: 09 Feb 2010
  • Loc: Olympia, WA

Posted 01 September 2021 - 06:38 AM

Wouldn’t bother with a surge protector.  If your going between buildings use fiber.  It’s immune to electrical interference and can run in the same conduent as power.  Take the fiber into your observatory to a dedicated switch that has a fiber interface built in.  Tons of switches that support this.  .  From there branch out to whatever you need.   I have 20 years of experience building networks. This will make your troubleshooting much easier and won’t cost much more.  As for conduent I wouldn’t go less than 2 inch.


  • MCinAZ likes this

#10 MJB87

MJB87

    Gemini

  • *****
  • Moderators
  • Posts: 3,067
  • Joined: 17 Feb 2014
  • Loc: Talbot County, MD & Washington, DC

Posted 01 September 2021 - 06:53 AM

I concur with the suggestion that fiber eliminates the need for a surge protector and, indeed, I make extensive use of buried fiber on my property. Fiber is the best option However, the poster has ruled out fiber so we need to deal with how to best make use of a wired Ethernet connection.

 

In that case, the one we are actually dealing with, I DO recommend a surge protector. You just install it toward at the end of your underground cable run between that point and the edge device, e.g., switch or router. You then ground it with its ground wire. You can find lots of example products by searching "Ethernet surge protector" on Amazon.



#11 mmalik

mmalik

    DSLR camera modifications

  • *****
  • Vendors
  • Posts: 12,254
  • Joined: 13 Jan 2012
  • Loc: USA

Posted 01 September 2021 - 07:53 AM

The whole nine yards of cabling and conduiting here.... Go small on the conduits because that translates to (large) holes you'll need to make on either side which can be a big problem. Don't pull; rather thread; read details in the link. Regards



#12 wboeck

wboeck

    Mariner 2

  • *****
  • topic starter
  • Posts: 297
  • Joined: 01 Dec 2004
  • Loc: Nebraska

Posted 01 September 2021 - 09:11 AM

I concur with the suggestion that fiber eliminates the need for a surge protector and, indeed, I make extensive use of buried fiber on my property. Fiber is the best option However, the poster has ruled out fiber so we need to deal with how to best make use of a wired Ethernet connection.

 

In that case, the one we are actually dealing with, I DO recommend a surge protector. You just install it toward at the end of your underground cable run between that point and the edge device, e.g., switch or router. You then ground it with its ground wire. You can find lots of example products by searching "Ethernet surge protector" on Amazon.

I am not completely against fiber. It appears that the conduit needs special bends and equipment on each side of the fiber. Would it work in regular 90 degree electrical pvc conduit going up into my concrete pedestal and in a J box for connecting to the side of the house? Is 2 inch conduit a must with fiber?

 

thanks,

Wayne



#13 MJB87

MJB87

    Gemini

  • *****
  • Moderators
  • Posts: 3,067
  • Joined: 17 Feb 2014
  • Loc: Talbot County, MD & Washington, DC

Posted 01 September 2021 - 09:42 AM

Hi Wayne,

 

Modern fiber has far more flexibility than the fiber of past decades. Check the specs. I'd personally have no issue with a 90-degree bend of a reasonably sized conduit. Some modern fibers have a bend radius of only 7.5mm (0.3 inches).  As for conduit, I'd not do anything less than 1.25" myself.

 

However, my "hard earned" experience suggests that you always pull at least two cables through. While my cables have held up very well, I've managed through personal incompetence to damage a couple of the connectors and it turns out to be difficult to install replacement connectors. So I'm glad to have a backup.

 

So if I were installing a new data connection, I'd run two fibers plus and backup Cat6 cable (which I would only attach in an emergency).

 

BTW, I had to connect two LAN switches only about 4 feet apart between my two adjoining observatory structures. I used fiber -- purely to help isolate them from surges.



#14 dghent

dghent

    Apollo

  • *****
  • Vendors
  • Posts: 1,197
  • Joined: 10 Jun 2007
  • Loc: Maryland

Posted 03 September 2021 - 08:35 AM

Pull 2 runs of 50/125 OM3 multimode fiber between house and observatory. This will let you run 1000BASE-SX and, if you desire later on, 10GBASE-SR over it. There are direct-burial versions of this cable available, too.

 

In the case of 1000BASE-SX, you can get small media adapters to take 1000BASE-T twisted pair and turn it into 1000BASE-SX. You can also get switches with SFP uplink ports built into them that can take a 1000BASE-SX transceiver, which you can terminate the fiber on instead. Not sure of your aptitude for networking, but there are a few ways to do your equipment on either end of the line.



#15 NearVision

NearVision

    Ranger 4

  • -----
  • Posts: 359
  • Joined: 23 Sep 2017
  • Loc: SE Wisconsin

Posted 03 September 2021 - 11:08 AM

I don't think this has been mentioned before but make sure that the low voltage conduit (cat6 or other cables) is at least 12-18" away from the 110/220 power conduit for as much of the run as possible. Even if you use shielded cables it will still pick up interference from the power cable. Also, count how many bends (45 or 90 deg) are in each conduit. Every bend reduces the 'real' fill for a conduit. If I remember correctly just 2 90 deg bends reduces the amount of wires that can be pulled by something like 20% or more.

 

As Doug mentioned, running power and low voltage cable in the same conduit is illegal in most areas. You don't want the chance of 2 wires have a small nick in the insulation and 110 meeting your network equipment on the cat6 cable.

 

for my 2 cents worth on grounding: Lightening strikes to short buildings are rare but do happen. A friend of mine left his Christmas light on the house 1 year instead of taking them down in the spring and that was the summer his house was hit with lightening. It left a burn line with larger spots around the whole house.  Ground the observatory building well. It's the tallest object in the area so it will be a target. Unless it's surrounded by tall trees and has a very limited sky. :)



#16 dghent

dghent

    Apollo

  • *****
  • Vendors
  • Posts: 1,197
  • Joined: 10 Jun 2007
  • Loc: Maryland

Posted 03 September 2021 - 07:21 PM

For those of you who are harping on having a mile's distance between power and data cables, you would likely have a stoke if you saw cable runs inside any typical, contemporary datacenter. Just saying. Ethernet noise rejection has come a long way since the larval age of 10Mb ethernet.

 

At any rate, fiber between buildings is the norm and completely removes multiple worries, from ground loops to surges to alien crosstalk and discombobulation from AC fields. Put a few runs of 50um OM3 multimode in the ground and call it a day. Light the same fiber up with 10Gb later if you desire.


Edited by dghent, 03 September 2021 - 07:23 PM.

  • OldManSky likes this

#17 wboeck

wboeck

    Mariner 2

  • *****
  • topic starter
  • Posts: 297
  • Joined: 01 Dec 2004
  • Loc: Nebraska

Posted 09 September 2021 - 01:11 PM

I don't think this has been mentioned before but make sure that the low voltage conduit (cat6 or other cables) is at least 12-18" away from the 110/220 power conduit for as much of the run as possible. Even if you use shielded cables it will still pick up interference from the power cable. Also, count how many bends (45 or 90 deg) are in each conduit. Every bend reduces the 'real' fill for a conduit. If I remember correctly just 2 90 deg bends reduces the amount of wires that can be pulled by something like 20% or more.

 

As Doug mentioned, running power and low voltage cable in the same conduit is illegal in most areas. You don't want the chance of 2 wires have a small nick in the insulation and 110 meeting your network equipment on the cat6 cable.

 

for my 2 cents worth on grounding: Lightening strikes to short buildings are rare but do happen. A friend of mine left his Christmas light on the house 1 year instead of taking them down in the spring and that was the summer his house was hit with lightening. It left a burn line with larger spots around the whole house.  Ground the observatory building well. It's the tallest object in the area so it will be a target. Unless it's surrounded by tall trees and has a very limited sky. smile.gif

I have them about 3 inches apart in separate pvc conduits



#18 NearVision

NearVision

    Ranger 4

  • -----
  • Posts: 359
  • Joined: 23 Sep 2017
  • Loc: SE Wisconsin

Posted 09 September 2021 - 05:11 PM

I have them about 3 inches apart in separate pvc conduits

I'm just repeating the recommendations. I've seen signal cables right next to power cables for long distances without any trouble. I also know that if you have noise on the power lines, which can happen easily, the farther away the signal cables are, the less likely that noise is to get transferred and cause problems. It all depends on how noisy the power line is and how much noise the signal lines can tolerate before the signal quality is affected.

 

On a new installation I'd rather separate them enough to minimize any possible problems instead of having to figure out how to filter the noise or have limited usage afterward.



#19 Christopher Erickson

Christopher Erickson

    Skylab

  • *****
  • Posts: 4,027
  • Joined: 08 May 2006
  • Loc: Waikoloa Village, Hawaii

Posted 10 September 2021 - 05:43 AM

1. NEVER run copper Ethernet cable between structures. Especially in plastic conduit. Too vulnerable to lightning, GPR and ESD.

 

2. Run fiber optics instead and use media converters on the ends.



#20 wotalota

wotalota

    Sputnik

  • *****
  • Posts: 28
  • Joined: 15 Aug 2016
  • Loc: SW New Hampshire

Posted 10 September 2021 - 03:24 PM

I had a short run of about 16 feet using a plastic conduit for power and another one for a single cat 6.

Electical inspection failed the install. Had to widen the trench so the two conduits were at least (I think) 12" apart and all the conduit exposed above ground had to be replaced by a higher/stronger grade then what was available at the local HD store. He also advised pulling a new Ethernet cable that was water proof, saying however well you think you have sealed the joints water will get inside. There were also things like how much sand had to surround the conduit before fill could be used. I appreciated the failing grade and fixed the issues before filling in.



#21 wboeck

wboeck

    Mariner 2

  • *****
  • topic starter
  • Posts: 297
  • Joined: 01 Dec 2004
  • Loc: Nebraska

Posted 10 September 2021 - 04:34 PM

I had a short run of about 16 feet using a plastic conduit for power and another one for a single cat 6.

Electical inspection failed the install. Had to widen the trench so the two conduits were at least (I think) 12" apart and all the conduit exposed above ground had to be replaced by a higher/stronger grade then what was available at the local HD store. He also advised pulling a new Ethernet cable that was water proof, saying however well you think you have sealed the joints water will get inside. There were also things like how much sand had to surround the conduit before fill could be used. I appreciated the failing grade and fixed the issues before filling in.

Thanks, hope I am able to keep them as is.



#22 mmalik

mmalik

    DSLR camera modifications

  • *****
  • Vendors
  • Posts: 12,254
  • Joined: 13 Jan 2012
  • Loc: USA

Posted 10 September 2021 - 05:07 PM

Maybe I should install 3/4" conduit for one cat 6 cable as originally proposed and take a chance by unplugging the cable from my router when not in use.

Anything you run will be actually legacy, CAT6 or fiber. Practically you should be using WiFi. Just run CAT6 in 3/4" conduit but try installing a robust WiFi you could connect to without having to use any physical connection. Regards


  • rgsalinger likes this

#23 wboeck

wboeck

    Mariner 2

  • *****
  • topic starter
  • Posts: 297
  • Joined: 01 Dec 2004
  • Loc: Nebraska

Posted 11 September 2021 - 02:20 PM

I had a short run of about 16 feet using a plastic conduit for power and another one for a single cat 6.

Electical inspection failed the install. Had to widen the trench so the two conduits were at least (I think) 12" apart and all the conduit exposed above ground had to be replaced by a higher/stronger grade then what was available at the local HD store. He also advised pulling a new Ethernet cable that was water proof, saying however well you think you have sealed the joints water will get inside. There were also things like how much sand had to surround the conduit before fill could be used. I appreciated the failing grade and fixed the issues before filling in.

I am planning on using direct burial for both cat6 and electrical in the PVC



#24 TheSheriff

TheSheriff

    Mariner 2

  • *****
  • Posts: 277
  • Joined: 15 Jul 2007
  • Loc: Duck Football Country

Posted 12 September 2021 - 04:16 AM

I had a short run of about 16 feet using a plastic conduit for power and another one for a single cat 6.

Electical inspection failed the install. Had to widen the trench so the two conduits were at least (I think) 12" apart and all the conduit exposed above ground had to be replaced by a higher/stronger grade then what was available at the local HD store. He also advised pulling a new Ethernet cable that was water proof, saying however well you think you have sealed the joints water will get inside. There were also things like how much sand had to surround the conduit before fill could be used. I appreciated the failing grade and fixed the issues before filling in.

If by "Plastic conduit" you mean PVC, electrical or otherwise, your inspector is nuts.  Over the years I have laid miles of PVC, both water and electric.  If done correctly, which a 6 year old could do with 30 seconds instruction, they will not leak.  Old school threaded pipe or metal conduit  is a different story.

 

And if water does get in, it would have to be condensation, not a leak.



#25 wotalota

wotalota

    Sputnik

  • *****
  • Posts: 28
  • Joined: 15 Aug 2016
  • Loc: SW New Hampshire

Posted 12 September 2021 - 08:34 AM

Yes PVC. No I think the inspector was fine, it was a question of complying with local building/electric code for buried power cables. Things like requiring a red warning tape in the trench. Best to be aware of local code to avoid rework.




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics





Also tagged with one or more of these keywords: Observatory



Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics