Continuing Operation
6-
59
Speed Search
The speed search function finds the actual speed of the motor that is rotating using inertia, and then starts
smoothly from that speed. When restoring power after a temporary power loss, the speed search function
switches connection from the commercial power supply, and then restarts the fan that is rotating using inertia.
Related Parameters
Parameter
Number
Name
Description
Setting
Range
Factory
Setting
Change
during
Operation
Control Methods
Display
V/f
V/f
with
PG
Open
Loop
Vector
1
Flux
Vector
Open
Loop
Vector
2
b3-01
Speed search
selection (cur-
rent detection
or speed cal-
culation)
Enables/disables the speed search
function for the run command and
sets the speed search method.
0:Disabled, speed calculation
1: Enabled, speed calculation
2: Disabled, current detection
3: Enabled, current detection
Speed Calculation:
When the search is started, the
motor speed is calculated and
acceleration/deceleration is
performed from the calculated
speed to the specified frequency
(motor direction is also searched).
Current Detection:
The speed search is started from
the frequency when power was
momentarily lost and the
maximum frequency, and the
speed is detected at the search
current level.
0 to 3
2
*1
No
A
A
A
No
A
SpdSrch at
Start
b3-02
Speed search
operating cur-
rent (current
detection)
Sets the speed search operation
current as a percentage, taking the
Drive rated current as 100%.
Not usually necessary to set. When
restarting is not possible with the
factory settings, reduce the value.
0 to
200
100%
*2
No
A
No
A
No
A
SpdSrch Cur-
rent
b3-03
Speed search
deceleration
time (current
detection)
Sets the output frequency decelera-
tion time during speed search in
1-second units.
Set the time for deceleration from
the maximum output frequency to
the minimum output frequency.
0.1 to
10.0
2.0sec
No
A
No
A
No
No
SpdSrch Dec
Time
b3-05
Speed search
wait time
(current detec-
tion or speed
calculation)
Sets the contactor operating delay
time when there is a contactor on
the output side of the Drive. When
a speed search is performed after
recovering from a momentary
power loss, the search operation is
delayed by the time set here.
0.0 to
20.0
0.2sec
No
A
A
A
A
A
Search Delay
