Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) Commissioning - ForGe Control - Manual (Page 50)

50 Rockwell Automation Publication 7000-IN012B-EN-P - June 2014
Chapter 4 Commissioning the Drive
Figure 35 - Snubber Capacitor Test (shown with SPS Board installed)
Refer to Table 1 on page 46 to determine the appropriate snubber capacitance
value for the current rating of the SGCT used.
The capacitance measured is actually affected by the snubber capacitor and other
capacitance in the circuit, including capacitance from the gate driver circuit. You
are actually looking for a consistent reading for all devices.
If the capacitor is out of tolerance, refer to publication 7000-UM202_-EN-P for
detailed instructions on how to replace the snubber capacitor.
Heatsink Heatsink
Snubber
Resistor Snubber
Capacitor
Sharing Resistor
J1
SPS Board
1 2
SGCT
Test Point
Snubber Capacitor Wire
Use Connector Terminal Screw
for Testing Snubber Capacitor
SGCT Cathode Wire
Snubber Test Point