Rockwell Automation 150 MNL/SMC DIALOG+/APP-PROD GUIDE - Manual (Page 157)

8-4 Reduced Voltage Starting
Reduced Voltage (cont.) There are two methods of transition: Open Circuit Transition and
Closed Circuit Transition. Open circuit transition means that th
motor is actually disconnected from the line for a brief period of time
when the transition takes place. With closed transition, the motor
remains connected to the line during transition. Open circuit
transition will produce a higher surge of current because the motor is
momentarily disconnected from the line. Examples of open and
closed circuit transition currents are shown in Figure 8.3 and
Figure 8.4.
Figure 8.3 Open Circuit Transition
Figure 8.4 Closed Circuit Transition
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