L2: Power Loss Ride Through - Omron Q2A Series Technical Manual

Note:
• Display is in these units:
–Models4002 to 4023: 0.01 A
–Models 4031 to 4675: 0.1 A
• When the current level > 0.0 A, you cannot set this value < 10% of drive rated current.
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L1-13 Motor oL1 Memory Selection
No.
Name
(Hex.)
L1-13 Motor oL1 Memory
Selection
(046D)
0 : Disabled
1 : Enabled
Sets if the drive will calculate the motor again when the drive is energized again.
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L2: POWER LOSS RIDE THROUGH

L2 parameters set the drive operation during momentary power loss and the KEB Ride-Thru function method of
operation.
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KEB Ride-Thru Function
KEB is an acronym for Kinetic Energy Backup. If the drive detects a power loss or momentary power loss, it will
quickly decelerate the motor. The drive uses regenerative energy from the motor to keep the main circuit
operating. When you return power during motor deceleration, the drive returns operation to the status before the
power loss.
The KEB Ride-Thru function is different than other functions for continuous operation. If the drive detects
momentary power loss, the motor will ramp to stop. It will not coast to stop. This function is applicable for
applications in which it is necessary to prevent materials from running out, for example control for film and fiber
lines. The KEB Ride-Thru function has 4 methods of operation. Parameter L2-29 [KEB Method] sets the method.
When you use the KEB Ride-Thru function with one drive, set L2-29 = 1, 2 [Single KEB1 Ride-Thru, Single
KEB2 Ride-Thru].
If deceleration in coordination with more than one drive is necessary, for example textile machinery line systems,
set L2-29 = 3, 4 [System KEB1 Ride-Thru, System KEB2 Ride-Thru].
L2-29 KEB Method
1 Single KEB1 Ride- The drive uses regenerative energy from the motor to keep the DC bus
Thru voltage at the level set in L2-11 [KEB DC Volt Setpoint] while it
adjusts the rate of deceleration.
The KEB operation continues while the drive adjusts the deceleration
rate with the setting of C1-09 [Fast Stop Time].
2 Single KEB2 Ride- The drive uses information about the inertia of the connected
Thru machinery to find the deceleration rate necessary to keep the DC bus
voltage at the level set in parameter L2-11.
The drive uses system inertia to calculate the deceleration time. You
cannot adjust this value.
3 System KEB1 Ride- The drive does not monitor the DC bus voltage. The drive decelerates
Thru at the KEB deceleration time set in L2-06.
Use L2-06 to set the time necessary to decelerate from the current
frequency reference to 0 Hz. More than one drive can decelerate and
keep a constant speed ratio between drives.
4 System KEB2 Ride- The drive uses the KEB deceleration time set in L2-06 to decelerate
Thru and it also monitors the DC bus voltage.
If the voltage level increases, the drive momentarily holds the
frequency to prevent an ov before it continues to decelerate.
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KEB Ride-Thru Start
When L2-01 = 1 [RideThru@PwrLoss = Enabled] and L2-50 = 2, 3, 4 [RidThruMode@PwrLoss = KEB Mode,
KEB Stop Mode, KEB Decel to Stop], the drive starts the KEB operation immediately after it detects a momentary
power loss. When one of these conditions occur, the drive will activate KEB Ride-Thru:
SIEPYEUOQ2A01A AC Drive Q2A Technical Manual
V/f CL-V/f OLV CLV AOLV
Sets the function that keeps the current electronic thermal protector value when the drive stops
receiving power.
Table 12.51 KEB Ride-Thru Function Operation Method
Operation
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
Configuration Precautions
• Set C1-09 correctly to prevent Uv1 [DC Bus Undervoltage] and ov
[Overvoltage].
• If the drive detects Uv1 during the KEB operation, decrease the
value set in C1-09.
• If the drive detects ov during the KEB operation, increase the value
set in C1-09.
• If the drive detects Uv1 during the KEB operation, increase the
setting value of L3-20 [DCBus VoltAdj Gain] and L3-21 [OVSup
Acc/Dec Gain].
• If the drive detects ov during the KEB operation, decrease the
setting value of L3-20 and L3-21.
Use the dynamic braking option with System KEB Ride-Thru 1.
If you cannot use the dynamic braking option, use System KEB Ride-
Thru 2.
12.8 L: PROTECTION
Default
(Range)
1
(0, 1)
743
12