bus bar short circuit current capacity & support design
bus bar short circuit current capacity & support design
(OP)
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
Thanks






RE: bus bar short circuit current capacity & support design
I found some useful info in the Copper Development Association's site & they have a CD for applications
Here's the link :www.cda.org.uk
hope it helps
RE: bus bar short circuit current capacity & support design
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
RE: bus bar short circuit current capacity & support design
RE: bus bar short circuit current capacity & support design
You can also find in a Switchgear Manual published by ABB in Germany
RE: bus bar short circuit current capacity & support design
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.