Rockwell Automation 7000L PowerFlex Medium Voltage AC Drive (C Frame) - Classic Control - Manual (Page 371)

Component Definition and Maintenance 6-27
7000 “C” Frame 7000L-UM300I-EN-P – June 2013
The Symmetrical Gate Commutated Thyristor (SGCT or device) with
attached circuit board is located within the PowerCage assembly.
SGCTs must be replaced in matched sets:
• 4160V systems use sets of 2
• 6600V systems use sets of 3
SGCTs can be removed and replaced without interrupting the cooling
fluid path.
To remove SGCTs, the following procedure is to be employed:
Adjusting Nut
DO NOT ADJUST calibration nut.
SGCT
Retaining
Screws
Indicating Washer
Figure 6.21 – Replacing the SGCT
The SGCT and associated control board are a single component. There
will never be a time when the device or the circuit board will be changed
individually. There are 4 LEDs on the SGCT, and the following table
describes their functions:
LED 4 Green
Solid Green indicates that the Power Supply to the Card is
OK
LED 3 Green
Solid Green indicates that the Gate-Cathode resistance is
OK
LED 2 Yellow
LED ON indicates the gate is ON, and Flashes alternately
with LED 4 while gating
LED 1 Red
LED ON indicates the gate is OFF, and Flashes alternately
with LED 3 while gating
Symmetrical Gate
Commutated Thyristor
Replacement