Symmetrical gate commutated thyristor replacement – Rockwell Automation 7000A PowerFlex Medium Voltage AC Drive (A Frame) - ForGe Control (PanelView 550) User Manual
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Component Definition and Maintenance 4-15
7000 “A” Frame
7000A-UM151D-EN-P – March 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:
• 3300V and 4160V systems use sets of 2
• 6600V systems use sets of 3
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 1 while gating
LED 1
Red
LED ON indicates the gate is OFF, and Flashes alternately
with LED 2 while gating
Do not adjust outside nut.
SGCT captive screws
Inside nut used for loosening
and applying load to assembly
Figure 4.13 – Replacing the SGCT
Symmetrical Gate
Commutated Thyristor
Replacement