B3: Speed Search - YASKAWA GA700 Series Technical Manual

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b2-18: Short Circuit Braking Current
No.
Name
(Hex.)
b2-18 Short Circuit Braking
Current
(0177)
The Short Circuit Braking current cannot be higher than the drive rated current, although you can use b2-18 to set
a higher current level. The maximum rated current is 120% when the drive is set for Normal Duty (C6-01 = 1
[Normal Duty Rating]). The maximum rated current is 150% when the drive is set for Heavy Duty (C6-01 = 0
[Heavy Duty Rating]).
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b3: Speed Search

The Speed Search function detects the actual speed of a coasting motor, then restarts the motor before the motor
stops. Use Speed Search in these conditions:
• To continue operation after momentary power loss
• To switch from commercial power supply to drive power
• To restart a coasting fan
For example, the drive output turns off and the motor coasts when there is a momentary loss of power. After you
return power, the drive does Speed Search on the coasting motor, and restarts the motor from the detected speed.
When you use a PM motor, enable b3-01 [Speed Search at Start Selection].
There are two types of Speed Search for induction motors: Current Detection and Speed Estimation. Use
parameter b3-24 [Speed Search Method Selection] to select the type of Speed Search.
Parameter settings are different for different types of Speed Search. Refer to
Parameter
b3-01 [Speed Search at Start Selection]
b3-03 [Speed Search Deceleration Time]
b3-05 [Speed Search Delay Time]
b3-06 [Speed Estimation Current Level 1]
b3-07 [Speed Estimation Current Level 2]
b3-08 [Speed Estimation ACR P Gain]
b3-09 [Speed Estimation ACR I Time]
b3-10 [Speed Estimation Detection Gain]
b3-14 [Bi-directional Speed Search]
b3-17 [Speed Est Retry Current Level]
b3-18 [Speed Est Retry Detection Time]
b3-19 [Speed Search Restart Attempts]
b3-24 [Speed Search Method Selection]
b3-25 [Speed Search Wait Time]
b3-26 [Direction Determination Level]
b3-27 [Speed Search RUN/BB Priority]
b3-29 [Speed Search Back-EMF Threshold]
b3-31 [Spd Search Current Reference Lvl]
b3-32 [Spd Search Current Complete Lvl]
b3-33 [Speed Search during Uv Selection]
b3-35 [Low Back EMF Detection Level]
b3-36 [High Back EMF Detection Level]
b3-54 [Search Time]
YASKAWA SIEPC71061705H GA700 Series Technical Manual
V/f CL-V/f OLV CLV AOLV
Sets the Short Circuit Braking Current as a percentage of the motor rated current.
Table 12.26 Speed Search and Related Parameters
Speed Estimation
b3-24 = 1
x
-
x
x
x
x
x
x
x
x
x
x
x
x
x
x
-
-
-
x
x
x
-
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
Table 12.26
12.3 b: Application
Default
(Range)
100.0%
(0.0 - 200.0%)
for more information.
Current Detection 2
b3-24 = 2
x
x
x
-
-
-
-
-
*1
x
x
x
x
x
x
-
x
-
x
x
x
x
x
-
657
12