1.8 L: Protection Functions
208 YASKAWA ELECTRIC SIEP C710606 10A YASKAWA AC Drive - V1000 PRELIM. Programming Manual
For more information, see H2-01 to H2-03: Terminal MA/MB/MC, P1/PC and P2/PC
Function Selection on page 157, Settings 13, 14, 15, and 16.
■ L4-05: Frequency Reference Loss Detection Selection
The drive can detect a loss of an analog frequency reference from input A1 or A2. Reference
loss is detected when the frequency reference value reduces for 90% within 400 ms.
Figure 1.83
Figure 1.83 Loss of Reference Function
To have a fault output trigger when frequency reference loss occurs, set H2-01, H2-02, or
H2-03 to “C”. Refer to Setting C: Frequency Reference Loss on page 164 for details on
setting the output function.
Parameter L4-05 selects the operation when a frequency reference loss is detected.
Setting 0: Stop
The drive will stop the motor.
Setting 1: Continue Operation with Reduced Frequency Reference
The drive will continue operation at the frequency reference value set in parameter L4-06.
When the external frequency reference value is restored, the operation is continued with the
frequency reference.
■ L4-06: Frequency Reference at Reference Loss
Sets the frequency reference level the drive runs with when L4-05 = 1 and a reference loss
was detected. The value is set as a percentage of the maximum frequency.
No. Name Setting Range Default
L4-05 Frequency Reference Loss Detection Selection 0 or 1 0
No. Name Setting Range Default
L4-06 Frequency Reference at Reference Loss 0.0 to 100.0% 80.0%
100%
400ms
Analog
frequency
reference
Loss of
Reference
output
time
80%
10%
ON
OFF