User Manual of EM730/EM730E Series Inverter The inverter is started at the starting frequency, following the DC braking (not suitable when F04.04=0) and pre-excitation (not suitable when F04.07=0). The starting frequency will change to the set frequency after the holding time. F04.00=1: start with speed tracking The inverter is smoothly started from the current rotation frequency of the motor, following the speed tracking (size and direction). In order to ensure the motor torque during the start, please set the appropriate starting frequency. To fully establish the magnetic flux during the motor start, the starting frequency should be maintained for some time.
The starting frequency F04.01 is not limited by the lower frequency limit. Before the inverter is started, the motor may be in the status of low-speed running or reverse rotation. If the inverter is started immediately, it may be subject to overcurrent protection. In order to avoid such protections, it is necessary to perform DC braking to stop the motor and then make the motor run in the set direction to the set frequency before the inverter is started. When F04.03 is set to different values, DC braking torques can be enabled. F04.04 is used to set the time to enable DC braking. The inverter will start running once the set time is up. If F04.04=0.00, DC braking is invalid during start.
★ DC braking is started as shown in Fig. 7-. 178 Function Default Function code name Parameter description Unit Attribute code setting F04.01 Start frequency 0.00 - 10.00 Hz 0.00 〇 F04.02 Start frequency hold time 0.00-60.00, 0.00 is invalid s 0.00 〇 Function code Default Function code name Parameter description Unit Attribute setting F04.03 Starting current of DC braking 0.0～100.0 (100.0 = Rated current of motor) % 100.0 〇 F04.04 Starting time of DC braking 0.00 - 30.00 s 0.00 〇