Thermo AC-4000, Руководство по эксплуатации и обслуживанию

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40
Operation
Dynamic braking
Warning
For frequent starts and stops, short the inhibit terminals,
decelerate to a minimum speed, or apply a dynamic brake to
the motor. Do not use any of these methods for emergency
stopping. They may not stop a drive that is malfunctioning.
Removing AC line power (both L1 and L2) is the only
acceptable method for emergency stopping.
Frequent starting and stopping can produce high torque. This
may cause damage to motors, especially gearmotors that are
not properly sized for the application.
Dynamic braking may be used to rapidly stop a motor
(Figure 17, page 40). For the RUN/BRAKE switch, use a two pole,
two position switch rated for at least 125 VDC, 6 amps. For the
dynamic brake resistor, use a 40 watt minimum, high power,
wirewound resistor.
Sizing the dynamic brake resistor depends on load inertia, motor
voltage, and braking time. Use a lower-value, higher-wattage
dynamic brake resistor to stop a motor more rapidly. Refer to Table
4 (page 40) for recommended dynamic brake resistor sizes.
Note: Models MM23201, MM23211, and MM23501 incorporate
dynamic braking in their designs.