Hitachi SJ Series User Manual page 327

Chapter 12
(Ex. 1)
Main Circuit P-N Voltage (V)
Power recovered
Main Circuit DC
Under Constant DC Voltage Control
[bA-30] = 02 or 03
(Deceleration and stop)
[IPS] Signal
Note) Depending on the proportional gain and
integral time settings, the main circuit DC
voltage level while the function is being
activated may be lower than [bA-32].
!
• Keep the settings for [bA-31] and [bA-32] to the
undervoltage recovery level (P-N voltage 180 V
(200 V class), 360 V (400 V class)) or higher. The
function will not be activated in case of
undervoltage.
• Make setting so that [bA-31] will be lower than
[bA-32]. If the difference between the settings for
[bA-31] and [bA-32] is great, setting the
proportional gain [bA-37] to be too large may
cause sudden acceleration immediately after this
function is activated and may cause overcurrent.
[bA-30]
[bA-31]
Voltage
Time
Time (sec)
Time
Power Recovery
ON
12-13-20
(Ex. 2)
Main Circuit P-N Voltage
(V)
Under Constant DC
Voltage Control
[bA-30] = 03
[bA-30] = 02
(Deceleration and stop)
[IPS] Signal
• When [bA-30] is 02 or 03, PI control is performed
so that the internal DC voltage will be constant.
• Setting the proportional gain [bA-37] to be large will
accelerate the response. However, setting it to be
too large will dissipate the control, tending to cause
tripping.
• Setting the integral gain [bA-38] to be short will
accelerate the response. However, setting it to be
too short will also tend to cause tripping.
• If the proportional gain [bA-37] is small, the motor
will trip due to undervoltage because the voltage
will drop immediately after the function is activated.
• If you would like to retry even if the power failure
may be relatively long, supply the P-N voltage to
R0 and T0.
Inverter Function
Power recovered
Main Circuit DC Voltage
[bA-32]
[bA-31]
Time
Power
Time
Recovery
ON