Toshiba G7 manual Search Method, Search Inertia, Drooping Gain

F314			F320
Search Method		Direct Access Number —	F314
Program ⇒ Protection Parameters ⇒ Retry/Restart		Parameter Type — Selection List
In the event of a momentary power outage, this parameter may be used to set		Factory Default — Normal
the starting point (frequency) of the scanning signal that is used to determine		Changeable During Run — No
the rotor speed or this parameter may be used to select the method used to
search for the speed of the rotor. See F301 and F312 for additional information
on this parameter.
Settings:
Normal
Start from 0.0 Hz
Start from Running Frequency
Option Board (ASD-SS)
PG
Search Inertia		Direct Access Number —	F315
Program ⇒ Protection Parameters ⇒ Retry/Restart		Parameter Type — Selection List
After a momentary power loss or the momentary loss of the ST-to-CC		Factory Default — 1.0
connection, this parameter sets the time for the commanded torque to reach its		Changeable During Run — No
programmed setting during the automatic restart. This function is in effect so		Units — Seconds
long as the Retry/Restart feature is enabled at F301.
Settings:
0.5	Sec. (fast)
1.0	Sec. (standard)
1.5	Sec.
2.0	Sec.
2.5	Sec.
3.0	Sec.
3.5	Sec.
4.0	Sec.
4.5	Sec.
5.0	Sec. (slow)
Drooping Gain		Direct Access Number —	F320
Program ⇒ Feedback Parameters ⇒ Drooping Control		Parameter Type — Numerical
This parameter sets the effective 100% output torque level while operating in		Factory Default — 0.00
		Changeable During Run — Yes
the Drooping Control mode. This value is the upper torque limit of the motor
being driven by a given ASD while operating in the Drooping Control mode.		Minimum — 0.00

Maximum — 100.0

Drooping

Units — %

Drooping Control, also called Load Share, is used to share the load among two or more mechanically coupled motors. Unlike Stall, which reduces the output frequency in order to limit the load once the load reaches a preset level, Drooping can decrease or increase the V/f setting of a motor to maintain a balance between the output torque levels of mechanically coupled motors.

Because of variances in gearboxes, sheaves, belts, motors, and since the speed of the motor is constrained by the mechanical system, one motor may experience more load than its counterpart and may become overloaded. Drooping Control allows the overloaded motor to slow down, thus shedding load and encouraging a lightly-loaded motor to pick up the slack. The goal of Drooping Control is to have the same torque ratios for mechanically coupled motors.

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