# Catenary calcs, software

### Catenary calcs, software

Catenary defines the shape of a line strung between two points. It is not the same math as a parabolic curve. I am looking for a program that will do catenary calculations to determine the change in sag of a line if the line is longer or shorter and takes into account the different elevations of the end points.

Can you help me find such a program??

Hope so.

Paul Cook, PLS
L. Paul Cook

### Re: Catenary calcs, software

Hey Coooky non of the young bucks would have heard about such a thing as catenary...

Do you have the fomula or do you really also need that ?

Twinnie

### Re: Catenary calcs, software

Catenary, never heard the term...

Hyperbolic cosine, yes too familiar back in the Calculus II (Integral Calculus) days.

I sent a message to a structural engineer friend that works on transmission lines all the time to see what software they are using.  I will let you know what he uses.

$\cosh x = \tfrac12\left(e^{x} + e^{-x}\right)$

My Mate Cooky  being of stone age vinatge like my self will think  different of your coshx . Tis a club in our era.. and adding an x well you have an x rated club....

Sorry could not resist... I last coshx (ed) over 40 years ago!

### Re: Catenary ?

Catenary:

http://mysite.du.edu/~jcalvert/math/catenary.htm

In the cantenery equation the weight is uniform along the length of the wire or chain. In a suspension bridge the weight is considered uniform along the bridge span and the length of the cable varies along the curve.

Factors to be considered include the temperature of the environment which gives a base temperature for the wire. However the current being transmitted also affects the temperature and the wire becomes longer with greater sag. The actual composition of the wire also affects the stretch.

I am not sure the power companies would give a surveyor sufficient information to calculate the results precisely, tread lightly.

Paul in PA

### Re: Catenary calcs, software

PLS-CADD is the product they use.  Hope it helps.