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Snubber resistance (scr device) – Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - ForGe Control (PanelView 550) User Manual

Page 277

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Rockwell Automation Publication 7000-UM151E-EN-P - January 2013

277

Snubber Testing Appendix C

Snubber Resistance (SCR Device)

Access to the snubber resistor is not required to test the resistance. The snubber
circuit test point is located within the PowerCage under the heatsinks. For each
device, there is one test point. To verify the resistance, measure the resistance
between the test point and the heatsink above.

Figure 260 - Snubber resistance test

Refer to

Figure 15 on page 272

to determine the appropriate snubber resistance

value for the current rating of the SCR used.

If the resistor is found to be out of tolerance, refer to

Component Definition and

Maintenance on page 23

for the snubber resistor assembly replacement

procedure.

Resistance value between Test Point
and heatsink to its left is snubber resistance

Heatsink

Heatsink

Sharing Resistance

Snubber Resistance

Snubber Capacitor

Testpoint

To Gate

Driver Board

Heatsink

Heatsink