Cable Size Calculation

Option 1:

• Obtain a copy of the relevant national electrical standard (for example BS7671 in the UK, also applicable to Eire and Singapore)
• Read it
• Inwardly digest the contents
• Apply the contents

Option 2:

• Hire someone who can carry out option 1 somewhat faster.

It depends on the supply type, voltage, configuration of equipment....You might have to run several parallel circuits....or possibly a busbar run in a subterranean pipe chase....The first thing I would try to have the original run extended by whomever is supplying the power....

What will be the voltage drop per meter of busbar (with a given distance of separation between phases and single or multiple grouped together )carrying rated current?.

You trollin' me bub?

Table 4D1A/B (pages 332/333) or 4D3A/B (pages 335/6) of BS7671 Rev1 2011 will reveal all.
A/ gives CCC
B/ mV/A/M

I could have gone on past experience and been bang on put that would mean me telling you the answer.
Added to which, I had to buy the damn book.

I could look in the American codes but I can't be bothered.

No problem Tony. It is very simply. You can look in NEC [NFPA 70] /2011 ed. art.310 Table 310.15(B) 16:

Table 310.15(B)(16) Allowable Ampacities of Insulated Conductors Rated Up to and Including 2000 Volts, 60°C Through 90°C (140°F Through 194°F), Not More Than Three Current-Carrying Conductors in Raceway, Cable, or Earth (Directly Buried), Based on Ambient Temperature of 30°C (86°F):

For 2000 A 4*750 MCM [400 sqr.mm] copper conductor XLPE/EPR insulated.

In order to calculate voltage drop you need the reactance- depending on cable lay-out- and the power factor .

However DIN/VDE 0276-603 recommends 663 A underground for 3*400 sqr.mm [3 single-core cables]. Since no voltage is indicated then shield losses could to be introduced also. But French HN-33-S-52 permits 1090 A [in summer] underground 1000 sqr.mm copper[pvc insulated 70 oC] for 72 kV or more.I still don't know what GOST requirements are.

I recommend-strongly-the second option underlined by PWSlack.

100ea of #12 THHN wires in parallel and electrical tape or wire ties bundling them together. This arrangement will certainly be easier to pull through conduit if that is how you will be holding it in place.

Good Luck, Old Salt

Play with this and you will get some idea of the cable size you need to shunt that 2000A along.

Cable sizing compiles with BS 7671:2008 (IEE Wiring Regulations Seventeenth Edition) and IEC 60364:2001 - See more at: http://myelectrical.com/tools/cable-sizing-calculator#sthash.p4CJ5elZ.dpuf

Then check your local codes to verify

I punched in some numbers and got 630mm² x 2 in parallel with 8.6% voltage drop. Cu.

Al bigger still.

That's in free air.

Underground or in conduit derates it outside the cable size range.

This is a regular question being asked in this forum and I have replied it many times. Why you do not refer previous threads before putting up this thread again and again.

The design of cable size is basic knowledge of an Electrical Engineer and depends on various factors like type of cable being used like PILC, PVC , XLPE etc. Type of cable lying conditions like in trench, cable tray in air, covered by earth, the voltage, ambient temperature, and many more factors. So unless you specify the details no one can give you a proper technical answer.

The cable manufacturers provide the required information and rating of their cable and you can easily calculate the size of the cable required to be used.

Go to any cable manufacturers site they will give you sufficient data to find out your requirement.

Please provide the following data:-

1. Supply Voltage

2. Duty factor

3. Power factor

4. Permissible voltage drop

5. Cable laying details

6. Soil details

7. Ground/Air temperature

I agree with HiTekRedNek (#7 Comment); not only you are not in conditions to design that cable size, you don`t know how you must to ask. You didn`t make a complete ask; ¿DC or AC? ¿Voltage?

See numerous previous threads on CR4 for this commonly-asked question.

are you designing or choosing a cable?