Hitachi SJ Series User Manual page 318

Chapter 12
12.13.7 Restarting upon recovery after
instantaneous power failure
Q
• Main power was momentarily turned off due to
instantaneous power failure.
• I want to make restart setting while maintaining the
control power supply in standby by inputting the
P-N voltage into the control circuit.
• I want to connect a 24-V backup power supply to
be able to restart even if the power supply failed.
A
• When the power supply shows the voltage falling
short of the undervoltage level, you can select
either tripping ([bb-20] = 00) by recovering the
power supply or retrying restarting ([bb-20] ≠ 00).
• If the input power supply to the inverter is input
separately to main power supply (R, S, T) and
control power supply (R0, T0), the instantaneous
power failure is detected based on how much the
power to the main power supply (R, S, T) drops.
• When [bb-27] = 00, you can avoid instantaneous
power failure error before the control power supply
is turned off for saving energy while the inverter
output is being stopped.
• When [bb-27] = 02, you can avoid instantaneous
power failure error caused by power shutdown
during deceleration and stop.
Parameters
Item
Instantaneous power
failure tripping selection
Instantaneous power
failure/undervoltage retry
selection
Instantaneous power
failure allowable time
Instantaneous power
failure/undervoltage retry
standby time
Instantaneous power
failure/undervoltage
tripping selection during
stop
(Ex. 1) When [bb-20] = 00, tripping occurs
Control Power Supply
Inverter
Output
Motor Speed
[AL]
Parameter Data
0~16/ ∞(255)
[bb-20]
(Counts)
00
01
[bb-24] 02
03
04
[bb-25] 0.3~25.0(s)
[bb-26] 0.3~100.0(s)
00
01
[bb-27]
02
IP error occurs
Free Running
12-13-11
!
• The judgement of instantaneous power failure of
the inverter is based on the detection of voltage
drop in the main power supply (R, S, T).
• Depending on the fluctuation rate of the main
power supply (R, S, T), errors other than
instantaneous power failure may occur.
• If the input power supply to the inverter is input to
the control power supply (R0, T0) via main power
supply (R, S, T), undervoltage tripping or
undervoltage retry may be triggered first depending
on the operating situation.
• When the power supplied to the control power
supply (R0, T0) is shut off, the power will be lost as
quick as in about 80 ms. In this case, it will be a
power shutdown.
Description
Sets the retry counts in case of instantaneous power failure.
If this is set to 0, the motor will trip upon recovery from instantaneous
power failure.
Restarts at 0 Hz
Restarts with the frequency matching
Restarts upon frequency pull-in
Detection speed (frequency) <v2.00 or higher>
Trips after decelerating and stopping with the frequency matching
Restarts if the instantaneous power failure time is within the set value.
Starts after waiting for the set time upon power voltage recovery.
Disabled
Enabled
Disabled during stop and deceleration stop
(Ex. 2) When [bb-20] ≠00 and [bb-24] = 00, it
restarts at 0 Hz.
Control Power Supply
Inverter
Output
Motor Speed
[AL]
*) The motor will trip after instantaneous power failure
allowable time.
Inverter Function
Instantaneous power
failure allowable time
Free Running
Retry Standby
Time