Plotting Motor Starting Curve on TCC

You can plot motor starting curves on the TCC plot by:

1. Opening the Coordination focus.
2. Selecting the motor and other items you want to include in the TCC plot.
3. Clicking Plot TCC.

Plotting Individual Motor Curve

The plot below shows a motor starting curve for a 50 HP motor as well as a solid state trip curve for a breaker. The motor starting curve parameters are specified in the Motor Data dialog. After plotting the TCC, you can open the Temporary Motor Data dialog and change the parameters for the motor starting curve.

Figure 1: TCC Plot for 50 HP Motor Start

Figure 2: Temporary Motor Data Dialog for TCC

Plotting Grouped Motor Curve

When plotting the starting curve for grouped motors, you need to specify the largest motor size in addition to other data required for individual motors. The plot assumes that the largest motor is starting and the rest of the motors are already operating at steady state. The current in the plot is calculated as follows:

During Acceleration:

Total Amps = Locked rotor amps of largest motor + FLA of the rest

After Acceleration:

Total Amps = Total FLA of all the motor

Figure 3: Grouped Motor Data

The following plot shows the starting curves of two motors:

• Grouped motor with total of 500 HP and largest motor of 100 HP.
• Individual motor of 100 HP.

Figure 4: TCC Plot for 100 HP Individual Motor and 500 HP Grouped Motor

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