Snubber capacitance (scr device) – Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - ForGe Control User Manual
Page 85
Rockwell Automation Publication 7000-UM202B-EN-P - June 2014
85
Component Definition and Maintenance
Chapter 3
Snubber Capacitance (SCR Device)
Turn the multimeter from the resistance to capacitance measurement mode.
Proceed to verify the snubber capacitor by measuring from the test point and the
white wire at the 2-pole device snubber plug (labeled snubber).
Figure 78 - Snubber capacitance test
To test the snubber capacitance, disconnect the plug of the self-powered gate
driver board labeled SHARING and SNUBBER. The resistance between the
white wire of the plug and the Test Point to its left is the snubber capacitance.
Refer to
to determine the appropriate snubber capacitance
value for the current rating of the SCR used. Read the actual snubber capacitor
value shown in the table.
If the capacitor is out of tolerance, refer to
for the snubber capacitor
replacement procedure.
Heatsink
Heatsink
To Gate Driver Board
Heatsink
Heatsink
Snubber
Resistor
Snubber
Capacitor
Sharing Resistor
Test Point
Resistance value between test point and white
wire at 2-hole plug is snubber capacitance