Mitsubishi Electric FR-A700 Series, Technical Manual

Page: 273 / 550

307
2
P
ARAM
ETE
R
PARAMETER
2.10.5 Troubleshooting (torque control)
(A700)
A700
Case Cause Countermeasures
1
Torque control is not
exercised normally.
1)The phase sequence of the motor
or encoder wiring is wrong.
1) Check the wiring (Refer to page 86)
(2) The [
Pr. 800 Control mode selection
]
setting is improper.
(2)Check the [
Pr. 800
] setting. (Refer to page 252)
(3)The speed limit value is not input. (3)Set the speed limit value. (If the speed limit value is not
input, the motor will not rotate since the speed limit value is
regarded as 0Hz.)
(4) The torque command varies. (4)-1 Check that the command device gives a correct torque
command.
(4)-2 Decrease [
Pr. 72 PWM frequency selection
].
(4)-3 Increase [
Pr. 826 Torque setting filter 1
].
(5)The torque command does not
match the inverter-recognized
value.
(5) Recalibrate [
C16Terminal 1 bias command (torque/magnetic
flux)
, [
C17 Terminal 1 bias (torque/magnetic flux)
, [
C18
Terminal 1 gain command (torque/magnetic flux)
, [
C19
Terminal 1 gain (torque/magnetic flux)
. (Refer to page 320)
(6)Torque variation due to the change in
the motor temperature.
(6)Select magnetic flux observer by setting [
Pr. 95 Online auto
tuning selection
] .
(
Refer to page 276)
2
When the torque command
is small, the motor rotates
in the direction opposite to
the start signal.
The offset calibration of the torque
command does not match.
Recalibrate [
C16 Terminal 1bias command (torque/magnetic flux)
]
and [
C17 Terminal 1bias (torque/magnetic flux)
.] (Refer to page
320)
3
Normal torque control
cannot be exercised during
acceleration/deceleration.
The motor vibrates.
The speed limit is activated.
(Since the speed limit value changes
with the setting of the acceleration/
deceleration time [
Pr. 7, Pr. 8
] , the
speed limit may be activated.)
Reduce the acceleration/deceleration time.
Or, set the acceleration/deceleration time to "0". (The speed
limit during acceleration/deceleration depends on the speed
limit during the constant speed.)
4
Output torque is not linear
in response to the torque
command.
Insufficient torque. Return the [
Pr. 854 Excitation ratio
] to the initial value.