Download CFW500 - Programming Manual
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Functions Common to All the Control Modes P0320 – Flying Start (FS) / Ride-Through (RT) Adjustable Range: 0 = Inactive 1 = Flying Start 2 = Flying Start / Ride-Through 3 = Ride-Through Properties: cfg Factory 0 Setting: Access Groups via HMI: Description: Parameter P0320 selects the use of the Flying Start and Ride-Through functions. More details in the following sections. P0331 – Voltage Ramp for FS and RT Adjustable Range: 0.2 to 60.0 s Factory 2.0 s Setting: Properties: Access Groups via HMI: Description: This parameter determines the rising time of the output voltage during the execution of the Flying Start and Ride-Through functions. 11.4.1 Flying Start Function In order to activate this function, just program P0320 in 1 or 2; thus the inverter will impose a fixed frequency at the start, defined by the speed reference, and apply the voltage ramp defined in parameter P0331. In this way, the start current is reduced. On the other hand, if the motor is at rest, the speed reference and the real speed of the motor are very different or the direction of rotation is inverted; the result in such cases may be worse than the conventional start without Flying Start. The Flying Start function is applied on loads with high inertia or systems that require start with the motor spinning. Besides, the function may be deactivated dynamically by a digital input P0263 to P0270 programmed for “24 = Disable Flying Start”. In this way, the user may activate the function in a convenient way according to the application. 11.4.2 Ride-Through Function The Ride-Through function will disable the inverter output pulses (IGBT) as soon as the supply voltage reaches a value below the undervoltage value. A fault due to undervoltage (F0021) does not occur and the DC link voltage will slowly drop until the supply voltage returns. In case it takes the supply voltage too long to return (over 2 seconds), the inverter may indicate F0021 (undervoltage on the DC link). If the supply voltage returns before, the inverter will enable the pulses again, imposing the speed reference instantly (like in the Flying Start function) and making a voltage ramp with time defined by parameter P0331. Refer to Figure 11.7 on page 11-10. CFW500 | 11-9 11