78
Before operation
2) Each control gain is automatically set from the load inertia ratio estimated during acceleration/deceleration
operation and the
Pr. 818 Easy gain tuning response level setting
value.
Pr. 880 Load inertia ratio
is used as the initial value of the load inertia ratio for tuning. Estimated value is set in
Pr.
880
during tuning.
The load inertia ratio may not be estimated well, e.g. it takes a long time for estimation, if the following
conditions are not satisfied.
· Time taken for acceleration/deceleration to reach 1500r/min is 5s or less.
· Speed is 150r/min or more.
· Acceleration/deceleration torque is 10% or more of the rated torque.
· Abrupt disturbance is not applied during acceleration/deceleration.
· Load inertia ratio is approx. 30 times or less.
· No gear backlash nor belt looseness is found.
3) Press
or
to estimate the load inertia ratio or calculate gain any time. (The operation command for
external operation is the STF or STR signal.)
(2) Easy gain tuning execution procedure (
Pr. 819
= "2" load inertia manual input)
Easy gain tuning (load inertia ratio manual input) is valid only in the speed control mode under real sensorless vector
control or in the speed control or position control mode under vector control.
1) Set the load inertia ratio to the motor in
Pr. 880 Load inertia ratio
.
2) Set "2" (with easy gain tuning) in
Pr. 819 Easy gain tuning selection
. Then,
Pr. 820 Speed control P gain 1
and
Pr. 821
Speed control integral time 1
are automaticaly set by gain calculation.
Operation is performed in a gain adjusted status from the next operation.
3) Perform a test run and set the response level in
Pr. 818 Easy gain tuning response level setting
. Increasing the value will
improve trackability to the command, but too high value will generate vibration. (When "2" (parameter write enabled
during operation) is set in
Pr. 77 Parameter write selection
, response level adjustment can be made during operation.)
(3) Parameters automatically set by easy gain tuning
The following table indicates the relationship between easy gain tuning function and gain adjustment parameter.
REMARKS
· When "1 or 2" is set in
Pr. 819
and then returned the
Pr. 819
setting to "0" after tuning is executed, tuning results which are set in
each parameter remain unchanged.
· When good tuning accuracy is not obtained after executing easy gain tuning due to disturbance and such, perform fine
adjustment by manual input. Set "0" (without easy gain tuning) in
Pr. 819
.
Easy Gain Tuning Selection
(Pr. 819)
Setting
0
1
2
Load inertia ratio
(Pr. 880)
Manual input
a) Inertia estimation result (RAM) by
easy gain tuning is dispayed.
b) Set the value in the following cases:
• Every hour after power-on
• When a value other than "1" is
set in
Pr. 819
• When vector control is changed
to other control (V/F control etc.)
using
Pr. 800
c) Write is enabled only during a stop
(manual input)
Manual input
Speed control P gain 1
(Pr. 820)
Speed control integral time 1
(Pr. 821)
Model speed control gain
(Pr. 828)
Position loop gain
(Pr. 422)
Manual input
a) Tuning result (RAM) is displayed.
a) Gain is calculated when "2" is
set in
Pr. 819
and the result is
set in the parameter.
b) Set the value in the following cases:
• Every hour after power-on
• When a value other than "1" is
set in
Pr. 819
• When vector control is changed
to other control (V/F control etc.)
using
Pr. 800
b) When the value is read, the
tuning result (parameter
setting value) is displayed.
c) Write (manual input) disabled
c) Write (manual input) disabled
CAUTION
· Performing easy gain tuning with larger inertia than the specified value during vector control may cause malfunction such as
hunting. In addition, when the motor shaft is fixed with servo lock or position control, bearing may be damaged. To prevent these,
make gain adjustment by manual input without performing easy gain tuning.
Summary of Contents for FR-A741-11K
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