Short mast needed for Ethernet between buildings

[Techhead]

I need to run a 40 foot aerial ethernet messenger cable between two buildings.
The destination building is about 13 feet high but the source building is only about nine feet high at it's highest point so I need to raise the mounting point a couple of feet for adequate ground clearance.

Conduit/burial is not an option due to an existing sidewalks.

Is a standard 1-1/4 inch antenna mast up to the task or do I need something a bit heavier duty?

 

[Sparky19053]

If I was doing this I would be looking at a stick (10ft) of 1.5 heavy wall conduit, RSC. Its galvanized and will handle the stress. I'm going to assume you will be using a figure 8 cable with a messenger support cable? A good electrical supply house can set you up with the right stuff. Conduit, conduit hangers and some wedge clamps. Here is a page from HD Halex #6 - #2 Service Entrance (SE) Wedge Clamp Connector 51061 - The Home Depot.
BTW, we use 2" RSC for a home service drop and can easily stretch 80 to 100 foot with no deflection on the service mask. That is until a tree falls on the service drop and then all bets are off.

 

[Techhead]

If I was doing this I would be looking at a stick (10ft) of 1.5 heavy wall conduit, RSC. Its galvanized and will handle the stress. I'm going to assume you will be using a figure 8 cable with a messenger support cable? A good electrical supply house can set you up with the right stuff. Conduit, conduit hangers and some wedge clamps. Here is a page from HD Halex #6 - #2 Service Entrance (SE) Wedge Clamp Connector 51061 - The Home Depot.
BTW, we use 2" RSC for a home service drop and can easily stretch 80 to 100 foot with no deflection on the service mask. That is until a tree falls on the service drop and then all bets are off.

Thanks for your reply…yes, messenger cable with clamps.
Since the pipe will extend a couple of feet above the roof, I suppose a proper ground rod should be used.

 

[JNDATHP]

Another thing to think about is that the elevated wire could become a lightning rod of sorts.

 

[Techhead]

Another thing to think about is that the elevated wire could become a lightning rod of sorts.

Yes, probably will use something like this.

 

[Sparky19053]

Yes grounding the mask is important. Add a ground clamp to the mask, then run a piece of #12 or #10 solid wire to your existing ground rod for the home. Your not likley to find bare wire under a #8 size so figure in time the insulation on the #12 or #10 THHN ground will will peal off. With a figure 8 cable the messenger / guide wire is normally insulated so the cable is not as likely to attract lightning as you would think.
You know you can do a line of sight microwave antenna set up for about $150.00. I did one for a commercial shop, we passed three cameras and phone line over it flawlessly. No overhead cables in the way and no concern of falling trees.

 

[TonyR]

With a figure 8 cable the messenger / guide wire is normally insulated so the cable is not as likely to attract lightning as you would think.

I would not bet money on that.

Not sure about your locale, but you can't fool the lightning down here in the southeast U.S. (AL, GA, FL, MS, TN, etc., and even IN according to @looney2ns ) with any amount of insulation....it is Fierce with a capital F. And stringing metallic cable between 2 structures suspended by masts is an invitation to damage, all bonded and grounded adequately or not.

If there is Line Of Sight (LOS) between the 2 points to be spanned I'd go with a Ubiquiti Layer 2 Transparent Bridge.

I've installed over a dozen of them in the last several years and all are still working great but the Nanostations and Loco's of both 2.4 and 5GHz flavor have been hard to get or VERY expensive this past year or so. About the only one in stock right now is this one for $60, quite overkill for your distance but you can dial back the transmit power==>> Ubiquiti airMAX LiteBeam Gen 2 5AC 5GHz 23dBi CPE US

I hesitate to recommend a pair of the TP-LINK CPE210 radios even though I put one in a week ago on 1/28/23 and it's working great BUT....all my Ubiquiti installs have been running with no hiccups for over 8 years now...time will tell about the TP-LINK wireless bridge. I was between a rock and a hard place so I had to go with it.

If set up correctly the Ubiquiti Layer 2 Transp. Bridge will be like a CAT-5e cable, but without the distance limitations, will be a dielectric media that won't attract or conduct ESD / lightning damage but of course, cannot carry POE voltage.

Here's the schema I've used the last several years. The above Litebeams are different as far as configuration terms but the instructions above to the Ubiquiti airMAX Guide will make that distinction between "AC" devices (like the Litebeam above) and "M" devices (the type in my image below) when configuring.

 

[Techhead]

I would not bet money on that.

Not sure about your locale, but you can't fool the lightning down here in the southeast U.S. (AL, GA, FL, MS, TN, etc., and even IN according to @looney2ns ) with any amount of insulation....it is Fierce with a capital F. And stringing metallic cable between 2 structures suspended by masts is an invitation to damage, all bonded and grounded adequately or not.

If there is Line Of Sight (LOS) between the 2 points to be spanned I'd go with a Ubiquiti Layer 2 Transparent Bridge.

I've installed over a dozen of them in the last several years and all are still working great but the Nanostations and Loco's of both 2.4 and 5GHz flavor have been hard to get or VERY expensive this past year or so. About the only one in stock right now is this one for $60, quite overkill for your distance but you can dial back the transmit power==>> Ubiquiti airMAX LiteBeam Gen 2 5AC 5GHz 23dBi CPE US

I hesitate to recommend a pair of the TP-LINK CPE210 radios even though I put one in a week ago on 1/28/23 and it's working great BUT....all my Ubiquiti installs have been running with no hiccups for over 8 years now...time will tell about the TP-LINK wireless bridge. I was between a rock and a hard place so I had to go with it.

If set up correctly the Ubiquiti Layer 2 Transp. Bridge will be like a CAT-5e cable, but without the distance limitations, will be a dielectric media that won't attract or conduct ESD / lightning damage but of course, cannot carry POE voltage.

Here's the schema I've used the last several years. The above Litebeams are different as far as configuration terms but the instructions above to the Ubiquiti airMAX Guide will make that distinction between "AC" devices (like the Litebeam above) and "M" devices (the type in my image below) when configuring.

I hear ya about lightning...there are NO failproof solutions. I'm in PA and we get our share of thunderstorms. Most damage I've seen is due to differences in device grounds

I've also used Ubiquiti devices including their ETH-SP for static. There is no power at the remote building so it'll be PoE to power a Unifi Flex switch there.

 

[TonyR]

There is no power at the remote building so it'll be PoE to power a Unifi Flex switch there.

That's unfortunate. I made an incorrect assumption when you mentioned "sidewalks"...oh, well!

 

[ludshed]

How wide are the sidewalks? I’ll do a manual directional bore a couple times a year with just a shovel, drill and long flex bit.

 

[biggen]

Running Ethernet between buildings is asking induced voltage or lighting strikes at some point in the future.

Why not a wireless PTP links? I run a a couple of Nanobridges and those things are blazingly fast. Ahh, just saw there is no power at the remote building. Shame.

 

[The Automation Guy]

How wide are the sidewalks? I’ll do a manual directional bore a couple times a year with just a shovel, drill and long flex bit.

A DIY water jet works great too. It's basically a pipe that attaches onto a regular garden hose that necks down at the end to produce more water pressure. Daylight both sides of the sidewalk and then push the pipe from one hole to the other. You can cut the fittings off the ends of the pipe and convert it to a conduit pipe too or remove it and replace it with whatever pipe/wire you want to use.

 

[IReallyLikePizza2]

I would really not use ethernet for this, you're going to get burned! I would sooner run 120vac and fiber