Manual

6
You will now see a graphical representation of the busbar rack. MCS Star adds additional
busbar supports if the rack length exceeds the allowable support spacing.  is is based upon
the SCCR requirements and the size of the busbar. You will also notice that a bill of material is
being created on the left hand side of the window for all the components required to assemble
the system.
Note:  e center support was added because of the mechanical strength of the busbar.
It is based upon the graph below.
 e force between conductors is proportional to the square of the instantaneous current.
In case of a short circuit, which is protected by a short-circuit protective device (SCPD), the
maximum force occurs at the peak let-through current of the protective SCPD (circuit breaker or
fuse).  e higher the forces during a short-circuit are, the narrower the spacing between busbar
supports needs to be. Observe that the peak value of the s-c current is plotted on the y-axis.
 e maximum support distances for smaller cross-section conductors are given by pure
mechanical considerations, i.e. static loads and plugging forces.
Step 4:
Enter Supply Data
(continued)