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Precautions needed when running ethernet cable between two buildings.

We have two buildings that are approximately 200ft apart.  What precautions do I need to take when running an ethernet cable between both buildings with regards to differences between electrical potential, surge, lighting, etc?

Thank you
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Sr. Systems Engineer
First of all....the ethernet limit is approx 100m or 327 feet. Getting anywhere close to that and you start losing the ability to full duplex or run Gigabit over copper. If you are 200ft switch to switch you might be ok but if you have to route inside the buildings, total distance needs to be considered.

Fiber is better option albeit much more expensive. With transcievers and pretermed fiber, you could get out for under $1,000.

If you are okay there, are you planning running underground or aerial? Specific cable is available for both.... otherwise if you are going to use an existing box of cable, run nonmetallic conduit underground between the buildings and fische the cable in it.

Hope this helps.

At minimum, you'll need grounding on both ends of the cable that traverse the buildings.  Since Ethernet cable has copper, it is vulnerable to lightning strikes.  The grounding must be done before connecting the coupled wires to the switches.  200 ft may be marginal signal wise with the cable being exposed to potential outdoor interferences.

Alternatively, and more recommended, if it is in your budget, run fiber optic cable between the two buildings.  Fiber optic has no metal so it's immune to lightning strikes and other interferences.  There are heavy duty fiber cables specifically designed for outdoor use.  In both buildings, you'll have convertor boxes that convert the fiber optic to cat5 which you can plug into your switches or routers.
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This will be an aerial deployment and fiber is not an option due to the high cost.
Gary ColtharpSr. Systems Engineer
You need to get aerial cable with messenger wire. Use ground blocks at both ends... this is basically like stringing up a giant EMP catcher between the buildings. Build equipment replacement funds in to your budget.... fiber would be worth the money.

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