Delta Electronics VFD-F Series manual Group 6 Protection Function Parameters, Output frequency

VFD-F Series

5.7 Group 6: Protection Function Parameters

06 - 00	Over-voltage Stall Prevention		Factory Setting: 390.0/780.0
	Settings	230V series: 330.0	~ 410.0VDC
		460V series: 660.0	~820.0VDC

00: Disable

This parameter selects the voltage level for the Over-Voltage Stall Prevention function.

During decelerations, the DC bus voltage may exceed its maximum allowable value due to motor regeneration. When this function is enabled, the AC drive will stop decelerating and maintain a constant output frequency. The AC drive will only resume deceleration when the voltage drops below the preset value.

With moderate inertial loads, the over-voltage stall prevention will not occur and the deceleration time should be equal to Pr.1-10. With high inertial loads, the AC drive will automatically extend the deceleration time due to the step function shown below. If the deceleration time is critical for the application, then dynamic brake resistors should be used.

			Output frequency	Deceleration characteristic
				when Over-voltage stall
				prevention enabled
					Frequency held
					Time
				Deceleration Time
06 - 01	Over-current Stall Prevention during Acceleration					Factory Setting: 120
	Settings	20~150%				Unit: 1

This parameter selects the percentage of allowable over-current during acceleration before the stall prevention is enabled.

During acceleration, the AC drive output current may increase abruptly and exceed the value specified by Pr.06-01 due to rapid acceleration or excessive load on the motor. When this function is enabled, the AC drive will stop accelerating and maintain a constant output frequency. The AC drive will only resume acceleration when the current drops below the value set in Pr.06-01 (please see the graph below).

When the over-current stall prevention is activated, the acceleration time of the AC drive will be longer than the time set in Pr. 01-09.

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