suitable cable for catenary

[Jackflash]

Hi all, I've been asked to supply a large outbuilding thats to be used as offices via overhead catenary wire. The suspended length is about 50M. Does anyone have experience with this? My plan was to erect a telegraph pole half way and use 25mm 2 core SWA. Would something like split con cable be a better option? is it lighter?

Thanks

 

[buzzlightyear]

jumping jack flash ,could it not be put under ground ?or ask the DNO for a new supply to the offices .50mtrs is a long way
considering using 25mm SWA ,for that you would approx. two tel posts .

 

[suffolkspark]

Sounds a sure fire way to pull a gable end out of a house

 

[Jackflash]

Is split concentric lighter?

 

[Jackflash]

50m ? Be right. Just need a few of the missus' clothes props along the length.

Done anything similar?

 

[Jackflash]

jumping jack flash ,could it not be put under ground ?or ask the DNO for a new supply to the offices .50mtrs is a long way
considering using 25mm SWA ,for that you would approx. two tel posts .

It goes across a tarmac drive way. Could be possible to clip around some walls, trench the lawn then up a telegraph pole then catenary across the drive. .....its a care home.

 

[buzzlightyear]

to put any cable up 50mtrs you would need a cable winch .

 

[Jackflash]

what a bag of sugar.

lighter than SWA?

 

[Jackflash]

to put any cable up 50mtrs you would need a cable winch .

yes of course. i'd install 2x 25M catenary with a pole half way. The stone office is higher up so it would kind of just flop down to the main house

 

[davesparks]

Years ago hard-drawn copper singles were used for such overhead runs. If the overhead section is high enough to be ‘out of reach’ this should still be a viable option if you want to go this way

I’m inclined to suggest HO7-RNF flex or maybe NYY-J for this, I think the weight would be less than SWA.

 

[Marvo]

Several replies deleted. A bit of banter is fine but this is getting out of hand.

 

[freddo]

Years ago hard-drawn copper singles were used for such overhead runs. If the overhead section is high enough to be ‘out of reach’ this should still be a viable option if you want to go this way

This ^ Armoured cable would be impractical due to the weight. Split con is quite a good option, it is substantially lighter compared to armoured cable, and depending on distance between supports, you can do away with the messy catenary wire and just use some curly wurlies to attach the cable to the poles/walls.

 

[Octopus]

Who suggested overhead - you or the client?

 

[Marvo]

Overhead is problems for big supplies, find another way if possible.

 

[rsgaz]

With a 25m span, and the SWA cable mass at 1.625kg/m, you would need to pull it taught at 2500 newtons to make it sag less than 50cm in the middle, i.e. a quarter of a ton!!

If you wanted to keep the sag under 20cm, for example, then you'd need 6250 newtons.