Yaskawa AC Drive P1000 Bypass Technical Manual - Manual (Page 131)

n L3-25: Load Inertia Ratio
Determines the ratio between the rotor inertia and the load. Set this parameter when using Single Drive KEB 2
(L2-29 = 1 <1> ), Intelligent Stall Prevention during deceleration (L3-04 = 2), or the overvoltage suppression function
(L3-11 = 1).
No. Name Setting Range Default
L3-25 Load Inertia Ratio 1.0 to 1000.0 1.0
When set incorrectly, a fairly large current ripple can result during Single Drive KEB 2 (L2-29 = 1 <1> ). This may cause
overvoltage suppression (L3-11 = 1) or other faults such as ov, Uv1, and oC.
Calculate parameter L3-25 in the formula below:
L3-25 =
Machine Inertia
Motor Inertia
<1> Details on this function can be found in the standard P1000 Technical Manual (SIEPYAIP1U01) at www.yaskawa.com.
u L4: Reference Detection
These parameters set up the Loss of Frequency Reference function.
n L4-05: Frequency Reference Loss Detection Selection
The drive can detect a loss of an analog frequency reference from input A1, A2, or A3. Frequency reference loss is detected
when the frequency reference drops below 10% of the reference or below 5% of the maximum output frequency within 400
ms.
100%
400 ms
Analog
frequency
reference
Loss of
Reference
output
time
10%
ON OFF
Figure 5.34 Loss of Reference Function
Parameter L4-05 selects the operation when a frequency reference loss is detected.
No. Name Setting Range Default
L4-05 Frequency Reference Loss Detection Selection 0, 1 0
Setting 0: Stop
Drive follows the frequency reference (which is no longer present) and stops the motor.
Setting 1: Continue operation with reduced frequency reference
The drive will continue operation at the frequency reference value set to parameter L4-06. When the external frequency
reference value is restored, the operation is continued with the frequency reference.
n L4-06: Frequency Reference at Reference Loss
Sets the frequency reference level at which the drive runs when L4-05 = 1 and when detecting a reference loss. The value is
set as a percentage of the frequency reference before the loss was detected.
No. Name Setting Range Default
L4-06 Frequency Reference at Reference Loss 0.0 to 100.0% 80.0%
u L5: Fault Restart
After a fault has occurred, Fault Restart attempts to automatically restart the motor and continue operation instead of stopping.
5.8 L: Protection Functions
YASKAWA SIEP YAIP1B 01A YASKAWA AC Drive – P1000 Bypass Technical Manual 131
5
Programming