The selection of a dynamic brake resistor seems straight forward; however, there are important details to consider.  Two parameters must be specified to select a resistor, resistance (ohms) and power (watts).  The resistance determines the rate of which the resistor can absorb energy from the drive.  The power indicates how much energy can be absorbed during a finite amount of time.  Tables (below will specify the minimum resistance which can be connected to each drive based on drive model number.  Occasionally, a resistor can be reused from a previous drive; however, the minimum resistance must be check for the new drive.  DO NOT CONNECT A LOWER RESISTANCE TO A DRIVE THAN ALLOWED BY THE TABLE.

The power rating for a resistor is typically determined by its duty cycle.  This is calculated by looking at a ten minute time period.  During ten minutes, how many minutes will the drive be transferring energy to the resistor (regenerating).  Regeneration time divided by ten minutes will provide the duty of the resistor. Higher duty resistors are physically larger, generate more heat, and are more expensive. Call your drive specialist for discussion on the selection for complex applications.

PowerFlex 520-Series

VoltageHP NDkWMin ResistanceMax DB CurrentFrame
2400.50606.58A
24010606.58A
24020606.58A
240303212.34A
240501920.79B
2407.501920.79C
2401001526.3D
2401501526.3E
2402001135.9E
4800.50978.14A
48010978.14A
48020978.14A
48030978.14A
480507710.26B
4807.505514.36C
4801005514.36C
4801505015.8D
4802005015.8D
4802503026.33E
4803003026.33E

PowerFlex 750-Series

VoltageHP NDkWMin ResistanceMax DB CurrentFrame
4801-7901
4802-7901
4803-7901
4805-52.701
4807.5-31.601
48010-31.601
4801-31.6252
4802-31.6252
48020-31.6252
4805-31.6252
4807.5-31.6252
48010-31.6252
48015-22.634.92
48020-31.6253
48025-31.6253
48030-16.647.63
48040-15.8504
48050-15.8504
48060-7.91005
48075-7.91005
480100-3.3239.46
480125-3.3239.46
480150-3.3239.46
480200-3.3239.46
480250-2.43297
480300-2.43297
480350-1.65478.87