(2)Pr. 368 "feedback gain".

This parameter is valid when PLG feedback control is valid. Set if rotation is instable or response is slow.

When the setting is greater than 1, response is faster but overcurrent or rotational instability is more liable to occur.

When the setting is less than 1, response is slower but rotation is more stable.

(3)Instructions for PLG feedback control.

1)The number of motor poles used must be checked before starting operation. The number of poles set must be correct to ensure proper control of the motor.

2)The PLG should be coupled in line with the motor shaft without any mechanical looseness with a speed ratio of

1to 1.

3)Make sure that the PLG has been set to the correct rotation direction on the rotation direction display of the parameter unit. If the rotation direction is not correct, PLG feedback control cannot be carried out (the inverter can be operated).

4)During acceleration or deceleration, PLG feedback control is not performed to prevent instability such as hunting. PLG feedback control is started after the output frequency has once reached the [set speed] ￿ [speed feedback range].

5)If any of the following conditions occurs during PLG feedback control operation, the inverter is run at the output frequency of [set speed] ￿ [speed feedback range] without coming to an alarm stop and does not follow up the motor speed:

￿The pulse signal from the PLG is switched off due to an open cable, etc.

￿An accurate pulse signal cannot be detected due to induction noise, etc.

￿The motor is forced to accelerate (regenerative operation) or decelerate (e.g. motor lock) by large external force.

6)When opening the brake of the motor with brake, use the RUN (running) signal. (The brake may not be opened if the FU (output frequency detection) signal is used.)

7)During PLG feedback control, do not switch off the 5V power of the PLG. If the power is switched off, normal PLG feedback control cannot be exercised.

8)Programmed operation cannot be performed in the PLG feedback control mode (when the FR-A5AP is fitted).

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