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6-20 PARAMETER AND VARIABLE DESCRIPTIONS

1557-UM050F-EN-P – June 2013

CT Burden Line [CT burden line]

Linear number: 151

Minimum value: 1.0 ohms

Maximum value: 1000.0 ohms (FRN 5.xx)

6300.0 ohms (FRN 4.xx)

Default value: 15.0 ohms

This parameter specifies the value of the scaling resistors for the line current feedback.

To determine the required value for the scaling resistors, first calculate the equivalent scaling resistance using

the following formula:

R =

AmpsRatedMotor

RatioTVxC ..768.1

ohms

Because of hardware differences between the original Drive Control board and the new 18-pulse Drive Control

board, the actual value of resistor required depends on the firmware version:

For firmware revisions less than 5.00:

C.T. burden line =

249

249

ohms

For firmware revisions of 5.00 and above:

C.T. burden line = R x

rPulseNumbe

ohms

Select the nearest standard resistor value.

CT Burden Motor [CT burden motor]

Linear number: 152

Minimum value: 1.0 ohms

Maximum value: 1000.0 ohms (FRN 5.10)

6300.0 ohms (FRN 4.xx)

Default value: 39.0 ohms

This parameter specifies the value of the scaling resistors for the motor current feedback.

To determine the required value for the scaling resistors, first calculate the equivalent scaling resistance using

the following formula:

R =

AmpsRatedMotor

VxLEMRatio768.1

ohms

Because of hardware differences between the original Drive Control board and the new 18-pulse Drive Control

board, the actual value of resistor required depends on the firmware version:

For firmware revisions less than 5.00:

C.T. burden motor =

249

249

ohms

For firmware revisions of 5.00 and above:

CT burden motor = R ohms

Select the nearest standard resistor value.