User Manual EM303B General Purpose Inverter F3-24 Set the frequency for starting DC brake in the process of ramp-to-stop. Once the output frequency is lower than this frequency in the process of ramp-to-stop, if DC brake time≠0, then DC brake is enabled at stop. F3-25 Different setting values can define different DC brake torques at stop. If F3-25≤30.00, the percentage base is the rated output voltage of inverter. While, the DC brake controls the DC voltage generated by motor windings. If F3-25≥30.01, the percentage base is the rated output current of inverter Model G. While, the DC brake controls the DC current generated by motor windings.
F3-26 when DC brake command given by the terminal is active at stop or the output frequency reaches the setting value of F3 - 24 in the process of ramp-to-stop. DC brake enabled after the time set by F3-26 is up. F3-27 Set DC brake time at stop. If F3-27=0.00, the DC brake is disabled at stop. If there is a DC brake signal of external terminal at stop, then the DC brake time at stop takes the greater between the active time of the DC brake signal of external terminal at stop and the setting time of F3-27. The process of DC brake at stop is as shown in Figure 7-11. 1.
For heavy load, regular deceleration cannot stop motor fully due to inertia, and motor could be stopped by prolonging the DC brake time or increasing DC brake current at stop. 2. For potential energy load, DC brake current control mode cannot be applied due to the rising time of current. 108 No. Function Range Unit Default Type F3-24 DC Brake Start Frequency at Stop 0.10～60.00/0.1～60.0 Hz 2.00 〇 DC Brake Proportion at Stop 0.00～30.00, 30.01～250.00 % 100.00 〇 F3-25 DC Brake Waiting Time at Stop 0.10～30.00 0~15 kW S 0.40 〇 15~110 kW 0.70 F3-26 110~400 kW 1.00 F3-27 DC Brake Time at Stop 0.00～30.00 S 0.00 〇