Continuing Operation at Constant Speed When Frequency Reference Is
Lost
The frequency reference loss detection function continues operation using 80% speed of the frequency refer-
ence before loss when the frequency reference using a master speed analog input
400 ms.
When the error signal during frequency reference loss is output externally, set H2-01 to H2-05 (multi-function
contact output terminal M1-M2, P1-PC, P2-PC, P3-C3, and P4-C4 function selection) to C (frequency refer-
ence lost).
* Frequency references using the following master speed analog inputs are used to detect a frequency loss.
• Analog input using terminal A1
• Analog input using terminal A2 when H3-09 (Multi-function analog input terminal A2 function selection) is set
to 0 (Add to terminal A1).
Related Constants
Name
Con-
stant
Display
Number
Operation when
0: Stop (Operation follows the
frequency refer-
ence is missing
1: Operation at 80% speed
L4-05
指令丧失动作
Frequency reference is lost: Fre-
选择
quency reference dropped over
90% in 400 ms.
Setting
Description
Range
frequency reference.)
continues. (At 80% of speed
before the frequency reference
0 or 1
was lost)
*
is reduced 90% or more in
Control Methods
Change
Open
Factory
during
V/f
Loop
Setting
Opera-
V/f
with
Vector
tion
PG
1
0
No
A
A
A
Continuing Operation
MEMO
Open
BUS
Flux
Loop
Regis-
Vec-
Vector
ter
tor
2
A
A
49DH
71
6-