Snubber capacitance (scr device) – Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) Commissioning - ForGe Control User Manual
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Rockwell Automation Publication 7000-IN012B-EN-P - June 2014
Chapter 4 Commissioning the Drive
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 43 - 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
Table 2 on page 52
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 publicatio
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