Continuing Operation
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Continuing Operation at parameter Speed When Frequency Reference Is Lost
The frequency reference loss detection function continues operation at reduced speed using the set value in
parameter L4-06 as frequency reference value. When using an analog input as frequency reference, a fre-
quency reference loss is detected, when the reference value drops over 90 % in 400 ms or less.
When the error signal during frequency reference loss is output externally, set H2-01 or H2-02 (multi-function
contact output terminal M1-M2 and M3-M4 function selection) to C (frequency reference lost).
Related Parameters
Restarting Operation After Transient Error (Auto Restart Function)
If an Inverter error occurs during operation, the Inverter will perform self-diagnosis. If no error is detected, the
Inverter will automatically restart. This is called the auto restart function.
Set the number of auto restarts in parameter L5-01.
The auto restart function can be applied to the following errors. If an error not listed below occurs, the protec-
tion function will operate and the auto restart function will not work.
* When L2-01 is set to 1 or 2 (continue operation during momentary power loss)
Auto Restart External Outputs
To output auto restart signals externally, set H2-01 or H2-02 (multi-function contact output terminals M1-M2
and M3-M4 function selection) to 1E (auto restart).
Param-
eter-
Number
Name
Description
Setting
Range
Factory
Setting
Change
during
Opera-
tion
Access
Level
LCD Display
L4-05
Operation when fre-
quency reference is
missing
0: Stop
1: Operation (L4-06*fref@loss) inverter runs with reduced
speed.
Frequency reference is lost: Frequency reference dropped
over 90% in 400 ms.
0 or 1
0
No
A
Ref Loss Sel
L4-06
Output frequency adjust-
ment after freq. refer-
ence loss
If L4-05 is set to 1 and the reference is lost, inverter will
run at:
fout = L4-06*fref
before lossing.
0 – 100%
80%
No
A
Fref at Floss
• OC (Overcurrent)
• LF (Output phase failure)
• GF (Ground fault)
• OL1 (Motor overload)
• PUF (Fuse blown)
• OL2 (Inverter overload)
• OV (Main circuit overvoltage)
• OH1 (Motor overheat)
• UV1 (Main Circuit Undervoltage, Main Circuit MC Operation Failure)
*
• OL3 (Overtorque)
• PF (Main circuit voltage fault)
