How do you calculate bus bar size?

Answer 1

You just Calculate Size of Bus bar which has been mentioned below:

Example: Calculate Size of Bus bar having Following Details

• Bus bar Current Details:
• Rated Voltage = 415V,50Hz ,
• Desire Maximum Current Rating of Bus bar =630Amp.
• Fault Current (Isc)= 50KA ,Fault Duration (t) =1sec.
• Bus bar Temperature details:
• Operating Temperature of Bus bar (θ)=85°C.
• Final Temperature of Bus bar during Fault(θ1)=185°C.
• Temperature rise of Bus Bar Bar during Fault (θt=θ1-θ)=100°C.
• Ambient Temperature (θn) =50°C.
• Maximum Bus Bar Temperature Rise=55°C.
• Enclosure Details:
• Installation of Panel= Indoors (well Ventilated)
• Altitude of Panel Installation on Site= 2000 Meter
• Panel Length= 1200 mm ,Panel width= 600 mm, Panel Height= 2400 mm
• Bus bar Details:
• Bus bar Material= Copper
• Bus bar Strip Arrangements= Vertical
• Current Density of Bus Bar Material=1.6
• Temperature Co efficient of Material Resistance at 20°c(α20)= 0.00403
• Material Constant(K)= 1.166
• Bus bar Material Permissible Strength=1200 kg/cm2
• Bus bar Insulating Material= Bare
• Bus bar Position= Edge-mounted bars
• Bus bar Installation Media= Non-ventilated ducting
• Bus bar Artificial Ventilation Scheme= without artificial ventilation
• Bus bar Size Details:
• Bus bar Width(e)= 75 mm
• Bus bar Thickness(s)= 10 mm
• Number of Bus Bar per Phase(n)= 2 No
• Bus bar Length per Phase(a)= 500 mm
• Distance between Two Bus Strip per Phase(e)= 75 mm
• Bus bar Phase Spacing (p)= 400 mm
• Total No of Circuit= 3 No.
• Bus bar Support Insulator Detail:
• Distance between insulators on Same Phase(l)= 500 mm
• Insulator Height (H)= 100 mm
• Distance from the head of the insulator to the bus bar center of gravity (h)= 5 mm
• Permissible Strength of Insulator (F')=1000 Kg/cm2