Voltage across main circuit terminals P and N
VPN(V)
b052
b051 Undervoltage level
Output frequency (Hz)
b050: Controller deceleration and stop on power loss
b051: DC bus voltage trigger level during power loss
b052: Over-voltage threshold during power loss
b053: Deceleration time setting during power loss
b054: Initial output frequency decrease during power loss Integral time setting for nonstop operation at momentary power failure
b055: Proportional gain setting for nonstop operation at momentary power failure
b056: Integral time setting for nonstop operation at momentary power failure
Related code

Chapter 4 Explanation of Functions

4.2.91 Deceleration and stopping at power failure (nonstop deceleration at instantaneous power failure)

The nonstop deceleration at instantaneous power failure is the function making the inverter decelerate and stop the motor while maintaining the voltage below the overvoltage level when an instantaneous power failure occurs during the inverter operation.

You can select three modes with controller deceleration and stop on power loss (b050).

Item

Function code

Data or range of data

Description

 

 

00

Disabling the nonstop

 

 

deceleration function

 

 

 

Controller deceleration and stop on power loss

b050

01

Enabling the nonstop

deceleration function

 

 

 

 

 

02

 

 

 

03

 

DC bus voltage trigger level during power loss

b051

0.0 to 1000. (V)

 

Over-voltage threshold during power loss (*1)

b052

0.0 to 1000. (V)

 

Deceleration time setting during power loss

b053

0.01 to 3600. (s)

 

Initial output frequency decrease during power loss

b054

0.00 to 10.00 (Hz)

 

Proportional gain setting for nonstop operation at

 

 

Proportional gain at DC voltage

b055

0.00 to 2.55

constant control(Only when

momentary power failure

"02" or "03" is specified for

 

 

 

 

 

b050)

Integral time setting for nonstop operation at

 

0.0 to 9.999 /

Integral time at DC voltage

b056

constant control(Only when

momentary power failure

10.00 to 65.53

"02" or "03" is specified for

 

 

 

 

b050)

<1> nonstop deceleration at instantaneous power failure (b050=01)

-The nonstop deceleration at instantaneous power failure is the function making the inverter decelerate and stop the motor while maintaining the voltage below the overvoltage level (over-voltage threshold during power loss [b052]) when an instantaneous power failure occurs during the inverter operation.

-To use this function, remove the J51 connector cables from terminals R0 and T0, connect the main circuit terminals P and R0 to each other, and connect the main circuit terminals N and T0 to each other. Use 0.75 mm2 or heavier wires for the connections.

-If an instantaneous power failure has occurred while the inverter is operating the motor and the output voltage falls to the DC bus voltage trigger level during power loss (b051) or less, the inverter reduces the output frequency by the initial output frequency decrease during power loss (b054) once, and then decelerates the motor for the deceleration time setting during power loss (b053).

-If the voltage increases to an overvoltage level (exceeding the over-voltage threshold during power loss [b052]) because of regeneration, the inverter enters the LAD stop state until the voltage falls below the overvoltage level.

Note1:If the over-voltage threshold during power loss (b052) is less than the DC bus voltage trigger level during power loss (b051), the over-voltage threshold during power loss will be increased to the DC bus voltage trigger level during power loss when the stop level is applied. (However, the stored setting will not be changed.)

Note2:This nonstop deceleration function cannot be canceled until the nonstop deceleration operation is completed. To restart the inverter operation after power recovery, wait until the inverter stops, enter a stop command, and then enter an operation command.

Note3:Setting higher initial out put frequency decrease during powerloss (b054) results in over current trip due to sudden deceleration.

Setting lower b054, orlonger deceleration time during powerloss (b053) results in undervoltage trip due to less regeneration power.

Time (sec)

b054

b053

Time (sec)

4 - 83

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Image 141
Hitachi SJ700-2 instruction manual B054 B053