Mitsubishi FR-A5AP User Manual
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4.8. PLG Feedback Control
Make sure that Pr. 80 "motor capacity", Pr. 81 "number of motor poles", Pr. 144 "number of motor poles", Pr. 369
"number of PLG pulses", Pr. 359 "PLG rotation direction" and Pr. 370 "control mode" values are set properly. (Refer
to Section 4.6 "Pre-Operation Settings and 4.7 "Control Mode Setting".)
"number of PLG pulses", Pr. 359 "PLG rotation direction" and Pr. 370 "control mode" values are set properly. (Refer
to Section 4.6 "Pre-Operation Settings and 4.7 "Control Mode Setting".)
(1) Pr. 367 "speed feedback range".
This parameter is used to make the PLG feedback function valid.
Set the speed feedback control range.
(When Pr. 367 = 9999 (factory setting), the PLG feedback function is invalid.)
Set the speed feedback control range.
(When Pr. 367 = 9999 (factory setting), the PLG feedback function is invalid.)
<Setting>
Define the upper and lower limits in reference to the set value (frequency at which the motor is to be rotated at
constant speed). Normally, set the frequency converted from the rated motor speed (rated load) and slip (r/min).
Too large setting will result in slow response.
constant speed). Normally, set the frequency converted from the rated motor speed (rated load) and slip (r/min).
Too large setting will result in slow response.
Example: Rated speed of a 4-pole motor is 1740r/min (60Hz)
Slip Nsp
Slip Nsp
= synchronous speed - rated speed
= 1800 - 1740 = 60 (r/min)
= 1800 - 1740 = 60 (r/min)
Frequency equivalent to slip (fsp)
fsp =
Nsp - number of poles
=
60 x 4
= 2(Hz)
120
120
Speed feedback range
Set value
(Set command)
Driven load
Regenerative load