Rockwell Automation 7000A PowerFlex Medium Voltage Drive (A-Frame) - Classic Control - Manual (Page 510)

D-2 Meggering
7000A-UM150F-EN-P – June 2013 7000 “A” Frame
A T T E N T I O N A T T E N T I O N There exists the possibility of serious or fatal
injury to personnel if safety guidelines are not
followed.
The following procedure details how the Megger test on the
PowerFlex 7000A is to be performed. Failure to comply to this
procedure may result in poor Megger reading and damage to drive
control boards.
Equipment Required
 Torque Wrench and 7/16 inch socket
 Phillips Screwdriver
 2500/5000 Volt Megger
Procedure
1. Isolate and Lock Out the Drive System from High Voltage
Disconnect any incoming power sources, medium voltage
sources should be isolated and locked out and all control power
sources should be turned off at their respective circuit breaker(s).
Verify with a potential indictor that power sources have been
disconnected, also, the control power in the drive is de-energized.
2. Isolate the Power Circuit from System Ground (Float the
drive)
It is necessary to remove the grounds on the following
components within the drive (Refer to the electrical diagrams
provided with the equipment to assist in determining the points
which need to be disconnected):
 Voltage Sensing Boards (VSB)
 Output Grounding Network (OGN)
Voltage Sensing Boards
Remove all ground connections from all of the VSBs in the
drive. This has to be done at the screw terminals on the VSB
rather than the ground bus. There are two grounds on each
board marked “GND 1”, and “GND 2”.