bus bar short circuit current capacity & support design

[bab1]

Can anybody tell me how to calculate the short circuit current carrying capacity for bus bars & how to calculate busbar support distance in a switchboard. For 1000A, 50kA at 50°C what is is the preffered bus bar size if they are mounted edgewise.Kindly advice also if there is some software available for this purposes.

Thanks

 

[genRman]

bab1,
I found some useful info in the Copper Development Association's site & they have a CD for applications
Here's the link :

http://www.cda.org.uk

hope it helps

 

[jbartos]

Suggestions:
1. Check the more officical documentation: Standards, e.g.
1. NEMA BU-1 Busways
2. NEMA BU-1.1 General Instruction for Proper Handling, Installation,
Operation, and Maintenance of Busways Rated 600 Volts or Less
3. UL Std 857 Electric Busways and Associated Fittings
4. ANSI/IEEE C37.20 Switchgear Assemblies Including Metal-Enclosed Bus
5. ANSI/IEEE C37.23 IEEE Standard for Metal-Enclosed Bus and Calculating Losses in Isolated-Phase Bus
6. ANSI/NFPA 70 National Electrical Code
7. Visit

http://busbar.copper.org/ampacity/busbar.htm

8. Search this Forum. There are some excellent postings already

 

[ramvinod]

I will send detailed calculations to morrow.

 

[GRPatel]

You can use DIN VDE0103. It is about Mechanical and thermal short circuit strength of electric power installations.
You can also find in a Switchgear Manual published by ABB in Germany

 

[MDom]

bab1, as addition to the other mails,I know that each manu
facturer has it's own calculation for the diferent types of
swithdoad,presented in the table form for convenience.
For example, Schneider Electric in it's catalog for PRISMA P swchb proposes for 1000 A 1 bar/per phase with cross-section 80x5 mm for IP < 30 and 2 bars/phase with cross-section 50x5 for IP>31 - for 35C, for the higher temp.up to 50C derate 12% for IP 20 and 15% for IP 54.
The max.distance between busbar support center will be 125 mm. for 1 busbar (80x5) for 52 kA/1s ( case IP < 30) and
275 mm for 2 busbars ( IP>31). The distance between centre lines of phases and neutral busbar 75 mm. Other cases are in the catalogue.