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Delta Electronics AC Motor Drive VFD-E User Manual

Page 157

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Chapter 4 Parameters|

4-104

Revision June 2008, 04EE, SW--PW V1.11/CTL V2.11

DC Brake during Start-up is used for loads that may move before the AC drive starts, such as

fans and pumps. Under such circumstances, DC Brake can be used to hold the load in

position before setting it in motion.

DC Brake during stopping is used to shorten the stopping time and also to hold a stopped load

in position. For high inertia loads, a brake resistor for dynamic brake may also be needed for

fast decelerations.

08.04

Momentary Power Loss Operation Selection

Factory Setting: 0

Settings

0

Operation

stops

(coast

to stop) 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.

This parameter determines the operation mode when the AC motor drive restarts from a

momentary power loss.

08.05

Maximum Allowable Power Loss Time

Unit: 0.1

Settings

0.1 to 5.0 sec

Factory Setting: 2.0

If the duration of a power loss is less than this parameter setting, the AC motor drive will

resume operation. If it exceeds the Maximum Allowable Power Loss Time, the AC motor drive

output is then turned off (coast stop).

The selected operation after power loss in Pr.08.04 is only executed when the maximum

allowable power loss time is

≤5 seconds and the AC motor drive displays “Lu”.

But if the AC motor drive is powered off due to overload, even if the maximum allowable power

loss time is

≤5 seconds, the operation mode as set in Pr.08.04 is not executed. In that case it

starts up normally.

08.06

Base Block Speed Search

Factory Setting: 1

Settings

0

Disable

1

Speed search starts with last frequency command

2

Speed search starts with minimum output frequency (Pr.01.05)

This parameter determines the AC motor drive restart method after External Base Block is

enabled.