GE Industrial Solutions Entellisys Low Voltage Switchgear - Manuel (Page 27)

Entellisys Low Voltage Switchgear
27
All bolted bus joints should be made using the proper torque as
shown in Table A-1 in Appendix A of this manual.
Transformers not manufactured by General Electric may require
special mounting and bus connection hardware.
The neutral bus may be insulated from the grounded frame of the
switchgear equipment; thus, it is mounted on insulators throughout
the equipment. Installation of the neutral bus splice plate across a
shipping split is similar to the ground bar splice except that the
splice plate is not bolted to the equipment frame. Figure 4-11
illustrates the installation of the neutral splice plate.
Fig. 4-11. Plan view of neutral bus splice installation
The installation of the horizontal bus splice bars is with bolted joints.
Figures 4-12 and 4-13 illustrate the assembly of the main bus on the
bolted bus system. Copper bus systems are normally supplied with
flat washers and lock washers.
Figure 4-12 shows the rear view of the main bus area with the
installed indicated with cross-hatching.
Figure 4-13 shows that a spacer is used both between the bus bars
when more than one bar is used per phase (normally the 2500
ampere and larger main bus ratings) and over the outer bars of a
single or multiple bar joint.
After assembly of the main bars and spacers, the 1/2-13 bolts
should be tightened to a torque of 35-40 ft-lbs.
Fig. 4-12. Rear view of main bus at a shipping split
Fig. 4-13. Plan view of a three bar main bus connection