Hitachi WJ Series User Manual page 291

Chapter 9
Current position at power off save function
A
 When "Save current position at power off [P081]" is set to "Enable (01)", the value of "Current
position monitor [d030]" is stored in the inverter memory when the power is interrupted, and the
stored value is used as the current position when the power is on again.
 If the motor rotates while the power is interrupted, the position is not counted at that time,
!
resulting in position misalignment. Therefore, when activating this function, use a brake or other
means to prevent the motor from rotating when the power is interrupted.
 Even when the motor movement is restrained by a brake when the power is interrupted, the
position misalignment may accumulate due to the rotating shaft backlash, etc. Therefore, check
the operation of the application, and eliminate the position misalignment by using the power
return function or other means if necessary.
Code
Save current
[P081]
position at power off
Current position at
[P082]
power off
Item
Disable: Does not save the position data when the power
is interrupted.
Enable: Stores the current position when the power is
interrupted, and uses the stored position as the
current position when the power is on again.
This is the storage parameter for saving the position data
when the power is interrupted.
(The setting range is limited to "Position control range
(reverse) [P073]" to "Position control range (forward)
[P072]".)
9-14-11
Inverter Functions
Description Data
00
01
[P073]
to
[P072]