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NTT 240/460
Operation mode
Installation and user guide
Rev: 4.0
6.17.3 Sensorless loop tuning
!
ATTENTION:
•
default data do not guarantee a correct sensorless tuning for any motors and must be used only for
initial conditions of the tuning procedure.
•
during procedure, drive could lose motor control engage and lead to an overrun rotation or to an
unexpected shutdown. Please take safety relatated actions.
For sensorless tuning procedure, it’s necessary to observe the following variables into Scope function of Caliper
software:
•
current reference
•
measured current.
•
speed reference.
•
measured speed.
»
INITIAL PHASE: disconnect load and verify the correct motor phase connection.
1. set an internal speed reference whose value must be positive and lower than default initial speed; so, for
example, 50RPM.
2. enable the OPERATION ENABLE command neighter with digital input or with Caliper software.
3. ensure that motor rotate in clockwise viewing it from shaft; otherwise turn off the drive and invert two
phases of motor, then re-execute 1-2-3 instruction points.
»
MIDDLE PHASE: tuning with no load.
4. set an internal speed reference whose value must be a bit higher than default initial speed; so, for example,
500RPM. In this condition, motor could rotate in a discontinuous way or even NOT rotate.
5. enable the OPERATION ENABLE command and ensure that speed reference is actually brought to the
desired value set into instruction point 4. Otherwise increase or decrease
Covariance current
parameter
;
it’s recommended to increase or decrease with steps of 2-5 units. The initial sensorless setting example is
shown below. In most cases:
•
for motor with a PHASE resistor lower than 0.8Ω and a PHASE inductance lower than 0.8mH, parameter
should be increased.
When target is reached, please do not exceed beyond with the parameter setting.
•
for motor with a PHASE resistor higher than 0.8Ω and a PHASE inductance higher than 0.8mH, parameter
should be decreased.
When target is reached, please do not exceed beyond with the parameter setting.
Содержание NTT 240
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