parallel cables

[keith@kbw]

can any help me, i need to install 200amp three phase supply at 135m long, i wish to run two smaller cable insted of one large size cable, so can any one tell how to calculate for parallel cables supply.

 

[Had8Lives]

Don't know if you will get a cable big enough for such a long run. Would probably be best running two 100A Supplies depending on what you are supplying.

 

[keith@kbw]

we are supplying a water teatment plant, which needs 120amps 3 phase+N and we have to run parallel cable plus earth cable, what i am looking for is formulas to calaculate cables sizes.

 

[Mac]

we are supplying a water teatment plant, which needs 120amps 3 phase+N and we have to run parallel cable plus earth cable, what i am looking for is formulas to calaculate cables sizes.

American Wire Gauge table and AWG Electrical Current Load Limits

 

[Rulin]

for your 200amp supply

185mm 4 core will be fine....(thats in the ground)
150mm 4core on tray (perforated)

hope that helps

 

[keith@kbw]

thank you all your help, but can one help me with the formulas and calulations ?

 

[benji]

are you saying 200a= 1x 185 4c or 2x 185 4c

yours benji

 

[Mac]

thank you all your help, but can one help me with the formulas and calulations ?

Don't think you will actually find any calculations but try this.
Electrical Reference- Electronic Formulas, Calculations, Design

 

[baldsparkies]

Max demand and diversity along with possibly power factor correction to be considered, The link below could prove usefull to you hope it helps.

cablecalculation

Also appendix 4 of the big red book will give you all you need with regards to calcs rating factors ect.

 

[Mac]

Max demand and diversity along with possibly power factor correction to be considered, The link below could prove usefull to you hope it helps.

cablecalculation

Also appendix 4 of the big red book will give you all you need with regards to calcs rating factors ect.

Looked at this link earlier on.You have to pay for this one.

 

[baldsparkies]

Looked at this link earlier on.You have to pay for this one.

Sorry Mac thought it contained a useable demo mate

 

[keith@kbw]

thank you all for information.

 

[benji]

I would think a 185mm is a bit over and without checking would have thought a 4c 120mm
would be ok or 2x 4c 70mm in parallel also i believe cables in a trench underground benifit from the natural cooling of the soil
yours benji

 

[keith@kbw]

thank you, for our information, but i need to show this on paper thats why i need calculation or formuas.

 

[Wotsit]

Do you have all the details of equipment you are connecting? Supply over 100A really should take into account Xl and Xc so a bit of j notation might be required. As for the two cables thing if your calcs ask for a 400mm2 cable for example and you want to use two for ease of installation just use 2 x 200mm2.