Toshiba E6580772 Manual Do Utilizador

E6580772③

21

3.2.5 Monitoring method for feedback amount

Motor rotation speed can be monitored.

The motor is equipped with status monitor which is displayed on the panel and analog monitor which used

analog output terminals (FM, AM terminals)

Set items① and②  for motor speed monitoring.

① Speed feedback (real-time value) (Unit: Hz/free unit)

 The real-time display of motor speed can be made (Monitor display setting: 6).

② Speed feedback (one-second filter) (Unit: Hz/free unit)

 The filtered motor speed (feedback value) is displayed. (Monitor display setting: 7).

The monitoring for the above① and②  is possible also in cases except for 

pt

=8 (PG feedback vector control

operation). For example, the monitoring can be used for confirmation of the initial PG feedback amount in open

loop (V/F operation and the like).

In order to monitor motor rotation speed in condition monitoring, it is necessary to change the setting for

extended parameters (f711 to f714).

Refer to <Monitoring Operating Condition) section of the inverter manual.

In order to monitor motor rotation speed by the analog output terminal, it is necessary to change the setting

for basic parameter (fmsl,fm ) and extended parameter (f670, f671).

Refer to (Meter Setting and Calibration) section of the inverter manual.

3.2.6 Accuracy of speed control

The accuracy of speed control with the PG feedback can be obtained by the following formulae.

Accuracy of speed control = Command frequency accuracy + feedback detection accuracy

Command frequency accuracy＝± 

0.01(Hz)

F (Hz)

c

×100×

1

2

［％］

(using digital command)

Feedback detection accuracy＝±

1

2

0 04

F P

PG PH

C

(

)

.

×

×

×

  × 100 × 

1

2

［％］

F

C

:

 

Inverter output frequency

P

: Number of motor poles

PG

: Number of PG pulses/rotation

PH

: Single Phase = 1,      Two-Phase = 4

0.04

: Response speed of 40ms