YASKAWA V1000 Technical Manual page 208

5.8 L: Protection Functions
Setting 2: Recover as Long as CPU has Power
Drive will try to restart as long as the CPU still has power. This allows for a longer ride-through time than setting L2-01
to 1. A Uv1 fault is not triggered. This setting should also be used if the KEB function is utilized.
Note: 1. The amount of time the drive is capable of recovering after a power loss is determined by the capacity of the drive. Drive capacity
determines the upper limit for L2-02.
2. A Momentary Power Loss Unit is available to allow for a longer momentary power loss ride through time in a 0.4 to 7.5 kW drive
(200 or 400 V class). This option makes it possible to continue running after up to two seconds of power loss.
3. When L2-01 is set to 1 or 2, and a magnetic contactor between motor and drive is used, be sure that the magnetic contactor is kept
close as long as the drive attempts to restart.
4. When L2-01 is set to 1 or 2, "Uv" will flash on the operator while the drive is attempting to recover from a momentary power loss.
A fault signal is not output at this time.
n
L2-02: Momentary Power Loss Ride-Thru Time
Set the time in which the power has to return before a Uv fault is tripped. This parameter is valid only if L2-01 = 1.
No.
L2-02
n L2-03: Momentary Power Loss Minimum Baseblock Time
Sets the minimum baseblock time when power is restored following a momentary power loss. This determines the time it
takes for the leftover voltage in the motor to dissipate. Increase this setting if overcurrent or overvoltage occur at the
beginning of Speed Search after a power loss or DC Injection Braking. If L2-03 > L2-02, then the drive will restart after
the time set to L2-03 has passed from the beginning of the power loss.
No.
L2-03 Momentary Power Loss Minimum Baseblock Time
n L2-04: Momentary Power Loss Voltage Recovery Ramp Time
Sets the time constant used to ramp up the voltage during Speed Search. The setting value determines the time for a change
from zero to the maximum voltage.
No.
L2-04 Momentary Power Loss Voltage Recovery Ramp Time
n L2-05: Undervoltage Detection Level
Determines the voltage at which a Uv1 fault is triggered or at which the KEB function is activated.
No.
<1>
L2-05
<1> Values are for 200 V class drives and must be doubled for 400 V class drives.
<2> This value is initialized when E1-01 is changed.
This setting rarely needs to be changed.
When setting L2-05 is lower than the default setting, be sure to install an AC reactor option to the input side of the power
supply to prevent damage to drive circuitry.
n Kinetic Energy Backup (KEB) Function
In case of a power loss, the KEB function can decelerate the motor and use the rotational energy of the machine to backup/
maintain the drive DC bus for a certain period of time. This allows the drive to continue running without interrupting the
output power during a momentary power loss. Once the power is restored, the drive smoothly returns to the same operational
state before the power loss occurred. The KEB function supports two different operation modes.
KEB 1
In this mode the drive decelerates the motor based on the deceleration time set in parameter L2-06/C1-09 in order to keep
the DC bus voltage level high. When the power supply returns, it uses the time set to L2-07 or the selected acceleration
time to accelerate back to the frequency reference.
208
Name
Momentary Power Loss Ride-Thru Time
Name
Name
Name
Undervoltage Detection Level
YASKAWA ELECTRIC SIEP C710606 16C YASKAWA AC Drive – V1000 Technical Manual
Setting Range
Determined by
0.0 to 25.5 s
Setting Range
Determined by
0.1 to 5.0 s
Setting Range
Determined by
0.0 to 5.0 s
Setting Range
150 to 210 V
Default
o2-04.
Default
o2-04
Default
o2-04
Default
<2>
190 V