Delta VFD-L-I Series, User Manual

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Chapter 4 Parameters
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VFD-L-I Series
4-46 Revision July 2009, SW V1.1
DC Braking during Start-up is used for loads that may move before AC drive starts, such as
fans and pumps. These loads may also be moving in the wrong direction. Under such
circumstances, DC Braking can be executed to hold the load in position before applying a
forward motion.
DC Braking during stopping is used to decrease stopping time and also to hold a stopped
load in position. For high inertial loads, a dynamic braking resistor may be needed for quick
decelerations.
08-04 Momentary Power Loss Operation Selection
Factory Setting: 0
Settings 0 Operation stops after momentary power loss
1 Operation continues after momentary power loss, speed search
starts with the Master Frequency reference value
2 Operation continues after momentary power loss, speed search
starts with the minimum frequency
08-05 Maximum Allowable Power Loss Time Unit: 0.1
Settings 0.3 to 5.0Sec Factory Setting: 2.0
During a power loss, if the power loss time is less than the time defined by this parameter, the
AC drive will resume operation. If the Maximum Allowable Power Loss Time is exceeded, the
AC drive output is then turned off.
08-06 Base Block Speed Search Unit: 0.1
Settings 0.3 to 5.0Sec Factory Setting: 0.5
When a momentary power loss is detected, the AC drive turns off for a specified time interval
determined by Pr.08-06 before resuming operation. This time interval is called Base-Block.
This parameter should be set to a value where the residual output voltage is nearly zero,
before the drive resumes operation.
This parameter also determines the searching time when performing external Base-Block and
fault reset.
08-07 Current Limit for Speed Search Unit: 1
Settings
30 to 200
％
Factory Setting: 150