Delta Electronics VFD-EL Group 6 Protection Parameters, 06.00, output frequency Frequency Held

			Chapter 4 Parameters
Group 6: Protection Parameters
06.00	Over-Voltage Stall Prevention		Unit: 0.1
	Settings 115V/230V series	330.0 to 410.0V	Factory Setting: 390.0
	460V series	660.0 to 820.0V	Factory Setting: 780.0

0Disable Over-voltage Stall Prevention (with brake unit or brake resistor)

During deceleration, the DC bus voltage may exceed its Maximum Allowable Value due to motor regeneration. When this function is enabled, the AC motor drive will not decelerate further and keep the output frequency constant until the voltage drops below the preset value again.

Over-Voltage Stall Prevention must be disabled (Pr.06.00=0) when a brake unit or brake resistor is used.

NOTE

With moderate inertia load, over-voltage stall prevention will not occur and the real deceleration time will be equal to the setting of deceleration time. The AC drive will automatically extend the deceleration time with high inertia loads. If the deceleration time is critical for the application, a brake resistor or brake unit should be used.

high voltage at DC side

over-voltage detection level

time

output frequency

Frequency Held

Deceleration characteristic when Over-Voltage Stall Prevention enabled

time

previous deceleration time

actual time to decelerate to stop when over-voltage stall prevention is enabled

Revision August 2008, 2ELE, V1.02 4-67