7
Instruction Booklet
IB48088
Effective July 2021
Instructions for Eaton’s 7.2 kV Ampgard AR
(arc resistant motor control center)
(Compliant to IEEE C37.20.7-2017)
EATON
www.eaton.com
1.6 Main bus
Ampgard AR line-up comes with a 15.3 in. (38.87 cm) tall main bus
enclosures mounted on top of the 80 in. (203.20 cm) tall vertical
sections. Main bus enclosure may consist of a 1000 A, 1200 A,
2000 A, or 3000 A rated main bus and/or 1000 A rated adjustable
frequency drive (AFD) bus. The standard bus is always insulated
and can be silver or tin plated. The main bus enclosure in a starter
section may include vertical bus drops to connect to the starter(s).
The main bus enclosure in an incoming line section may include
vertical bus drops to connect the incoming line cables. Options for
both the top and bottom entry motor cables are available.
Also, included in the main bus enclosure is the low voltage vertical
and horizontal wireways and medium voltage motor cable cableway.
The horizontal wireway can be accessed from the front of the
section by removing the ¼”-20 machine screws. During normal
operation the cover must be in place with proper hardware.
Bus splicing:
Connect the bus bars using the splice kit, including
maintenance free hardware, provided with the equipment. Tighten
the bolts to 34 ft-lb (33 N m). All bus splices must be installed
before the plenums are installed.
Figure 9. Main bus enclosures.
Figure 10. Horizontal wireway access covers.
Main bus enclosure
Main bus enclosure
(Shown with AFD bus option)
LV horizontal wireway
access cover