Rockwell Automation 1608M MegaDySC User Manual, 800 - 2400 A - Manual (Page 22)

22 Rockwell Automation Publication 1608M-UM002A-EN-P - September 2013
Chapter 5 Operation
Figure 7 - Schematic Diagram of Automatic Bypass Switchboard Power Circuit
Note: The 3-wire MegaDySC models have not been evaluated by Underwriter's Laboratories,
Inc.® for connection to a corner-grounded or ungrounded delta power source. Contact Technical
Support for assistance.
Transient Voltage Surge
Suppression Over voltage transient protection is provided on the output of the MegaDySC.
Indicator lights for each phase on the front of the TVSS panel (behind Bypass
cabinet top front panel) are illuminated under normal operation. In case of a
severe over-voltage transient event, internal fuses in the TVSS module may open.
If TVSS operation is compromised, one or more of the indicator lights will be
extinguished. A form C contact is provided inside the TVSS module for remote
fault indication, if desired. Refer to the TVSS user manual for details on accessing
that contact. If a fault is indicated, the TVSS disconnect fuse block (F25-F26-
F27-F34) may be opened to allow servicing of the TVSS module. Refer servicing
to qualified personnel.
Servicing Notes Refer servicing to qualified and factory authorized personnel. Opening the
MegaDySC cabinet door will shut down the MegaDySC system and force an
automatic mechanical bypass. Refer to manual bypass instructions to perform a
seamless transfer of power before opening the enclosure door for servicing.
CBI
TVSS
X3
X2
X1
L3 L2 L1 X3 X2 X1
To MegaDySC section(s)
L3
L2
L1
CBO
CBB
Earth
Ground
N (if 4-wire system) N
N
Utility Input (Line)
Output to load
WARNING: This enclosure contains energy storage devices. Dangerous voltages
may exist within this enclosure after AC power has been removed. Do not touch
any components within the enclosure if the red LEDs located above capacitor
banks are lighted. If the red LEDs do not extinguish within 5 minutes, close the
enclosure door and contact Technical Support.