Power circuit, Powerbrick (scr) testing, Powerbrick – Rockwell Automation 7763 Medium Voltage OneGear SMC Flex Motor Controller (10-15 kV) User Manual
Page 108: Power circuit on
108
Rockwell Automation Publication 7760-UM001D-EN-P - October 2014
Chapter 8
Troubleshooting
3.
For boards mounted with hardware, remove the hardware, taking care not
to drop anything onto other circuits. For boards with nylon stand-off
posts, squeeze the section above the board and carefully pull the board up
and off the post.
4.
Lift out the circuit board, and check that the replacement board is the
correct part number and revision before installation (see
). Install the new board by replacing the hardware,
or pressing down onto nylon stand offs. Connect all wires, cables and
connectors. Ensure that all switch and/or jumper settings on the new
board are identical to those on the old board, and correct for the
application.
Power Circuit
PowerBrick (SCR) Testing
If a power semiconductor is suspected of malfunctioning, it may be checked as
follows:
1.
Remove all power from the equipment.
2.
Measure DC resistance as follows:
Complete power pole (from line side to load side)
12 kV (5 PowerBricks) 100…145 k
15 kV (6 PowerBricks) 125…175 k
Note:
It may be necessary to isolate one side of the power pole by disconnecting
one of the flex braid connections at the top of the power pole assembly. Parallel
resistance paths may be created due to earthing connections, motor windings or
other connected equipment.
Variations may also be noted based on the devices used in different ratings of
PowerBricks. The key is to look for notable differences between individual
PowerBricks or power poles.
ATTENTION: The fibre-optic cables can be damaged if struck or bent sharply.
Some have a locking feature which requires pinching the tab on the connector
and gently pulling straight out. The component on the printed circuit board
should be held to prevent damage.
SHOCK HAZARD: To avoid shock hazard, ensure the main power has been
disconnected before working on the controller, motor or control devices. Verify
that all circuits are voltage free using a hot stick or appropriate voltage
measuring device. Failure to do so may result in burns, injury or death.