6
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Speed Search
The speed search function finds the actual speed of a motor that is coasting without control and then starts
smoothly from that speed. It is also activated after momentary power loss detection when L2-01 is set to
enabled.
Related Parameters
* 1. The factory setting will change when the control method is changed. (Open loop vector control factory settings are given.)
* 2. Factory settings depend on Inverter capacity. (The values shown are for a 200 V Class Inverter for 0.4 kW.)
Param-
eter-
Number
Name
Description
Setting
Range
Factory
Setting
Change
during
Opera-
tion
Access
Level
LCD Display
b3-01
Speed search selection
(current detection or
speed calculation)
Enables/disables the speed search function for the RUN com-
mand 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 sear-
ched).
Current Detection
The speed search is started from the frequency when power
was momentarily lost or the maximum frequency and the
speed is detected when the set search current level is reached.
0 to 4
2
*1
No
A
Slip Comp Gain
b3-02
Speed search operating
current (current detec-
tion)
Sets the speed search operation current as a percentage, taking
the Inverter rated current as 100%.
Not usually necessary to set. When restarting is not possible
with the factory settings, reduce the value.
0 to
200
120%
No
A
SpdSrch Current
b3-03
Speed search decelera-
tion time (current detec-
tion)
Sets the output frequency deceleration time during speed
search.
Set the time for deceleration from the maximum output fre-
quency to the minimum output frequency.
0.1 to
10.0
2.0 s
No
A
SpdSrch Dec Time
b3-05
Speed search wait time
(current detection or
speed calculation)
Sets the contactor operating delay time when there is a contac-
tor on the output side of the Inverter. 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
0.2 s
No
A
Search Delay
L2-03
Min. baseblock time
Sets the Inverter’s minimum baseblock time, when the inverter
is restarted after power loss ridethrough.
Sets the time to approximately 0.7 times the motor secondary
circuit time parameter.
If an overcurrent or undercurrent occurs when starting a speed
search or DC injection braking, increase the set values.
0.1 to 5.0
0.1 s
*1
No
A
PwrL Baseblock t
L2-04
Voltage recovery time
Sets the time required to return the Inverter output voltage to
normal voltage at the completion of a speed search.
Sets the time required to recover from 0 V to the maximum
voltage.
0.0 to
5.0
0.3 s
*2
No
A
PwrL V/f Ramp t
