Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - ForGe Control (PanelView 550) - Manual (Page 60)

60 Rockwell Automation Publication 7000-UM151E-EN-P - January 2013
Chapter 3 Component Definition and Maintenance
7. While grounded, remove the SGCT from its anti-static bag.
8. Clean the heatsink with a soft cloth and rubbing alcohol.
9. Apply a thin layer of Electrical Joint Compound (Alcoa EJC No. 2 or
approved equivalent) to the contact faces of the new SGCTs. Apply the
compound to the pole faces using a small brush, and then gently wipe the
pole face with an industrial wipe so that a thin film remains. Examine the
pole face before proceeding to ensure that no brush bristles remain.
10. Slide the SGCT into place until the mounting brackets contact the surface
of the heatsink.
11. Tighten the captive screws located in the brackets.
12. Follow procedure
Uniform Clamping Pressure on page 53 to clamp the
heatsinks to a uniform pressure.
13. Connect the power cable and fiber optic cables (do not exceed the bend
radius).
Replacing Silicon
Controlled Rectifier and
SCR Self-Powered Gate
Driver Boards (SPGDB)
Replacing the Silicon Controlled Rectifier (SCR) is similar to replacing the
SGCT, except that you can replace the SCR and circuit board independently of
one another.
1. Isolate and lock out all power to the drive.
2. Note the position of the fiber optic cables for reassembly.
IMPORTANT SGCTs come in matched sets in systems with more than one device per
leg. When replacing the device, you must replace all SGCTs in the set
even if only one has failed. Arrange the devices from left to right in sets
(i.e. set 1+2, 3+4, 5+6).
IMPORTANT Too much joint compound may result in contamination of other surfaces
leading to system damage.
ATTENTION: To prevent electrical shock, disconnect the main power
before working on the drive. Verify that all circuits are voltage-free using
a hot stick or appropriate voltage-measuring device. Failure to do so may
result in injury or death.