# Calculating maximum vertical rise for coax cable



## jscelsi (Oct 25, 2010)

How do I determine the maximum vertical distance a coax cable can be run?


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## PowermanX590 (Nov 3, 2010)

jscelsi said:


> How do I determine the maximum vertical distance a coax cable can be run?


I think it would be when the weight of the cable exceeds its tensile strength. You would need to know the unit weight of the cable (lbs/ft for example), its diameter, and the cables breaking strength.

I remember going a similar problem in college except that the cable was a steel wire. Using the some simple equations we proved that it would be impossible to build an elevator to space without first coming up with some new super strength materials.


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## Dexman PE (Nov 5, 2010)

jscelsi said:


> How do I determine the maximum vertical distance a coax cable can be run?


I would ask the obvious question: why can't the cable be braced, supported, or attached to a wall?


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## speedyox (Nov 5, 2010)

Dexman PE said:


> jscelsi said:
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> 
> > How do I determine the maximum vertical distance a coax cable can be run?
> ...


Perhaps it's being ran inside a plenum or conduit? Even if it's not, you need to know how far it can be run between supports, right?


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## IlPadrino (Nov 5, 2010)

jscelsi said:


> How do I determine the maximum vertical distance a coax cable can be run?


Run for what and how?


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## Bean PE (Nov 9, 2010)

speedyox said:


> Dexman PE said:
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> > jscelsi said:
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Zip-tie it every 10 floors to be safe and call it good.

The only _practical_ question of maximum run for coax relates to signal degredation.


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## Slugger926 (Dec 20, 2010)

Bean PE said:


> speedyox said:
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> > Dexman PE said:
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250' max run length for 735 coax and 450' for 734 coax for DS3's. This is to a DSX-3 panel with one standard cross connect. I have trouble shot projects that the run length from equipment to DSX-3 was okay, but provisioning left in 9 sets of cross connects at high db loss each before reaching the DSX-3 assignment to the other piece of equipment. When customers pulled out, provisioning pulled the customer off of the DSX-3 panel without removing the cross connects back to our original DSX-3 assignment for our equipment.


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