Motor Protection By I; T- Monitoring - BONFIGLIOLI Agile Operating Instructions Manual

7.10.6.2 Motor Protection by I

571 Operation Mode (I
To protect the motor against overload the I
This kind of motor protection is mainly used in servo technology.
When using servo motors the I
By integrating temperature-dependent parameters, measurable or known, the heating of a mathemati-
cal model is simulated. The kind of the I
This parameter is switchable via data set.
The I²t monitoring works by function (I
The monitored value is evaluated via a PT1 element with the thermal time constant of the stator.
If the output of PT1 element is bigger than 120%, then an error message is generated and the drive
switches off. The threshold of 120% prevents, that an overshoot leads to an immediate shutdown.
In the application should be avoided exceeding 100% capacity of the stator winding permanently.
The output of the first PT1 element is linked to the input of the second PT1 element which includes
the thermal motor time constant. This output may be permanently 100%.
This corresponds to the complete thermal capacity of the motor. If 102% is reached, the drive
switches off with an error message. Both outputs are connected to the adjustable alarm limit.
571
Operation Mode
42 – I²t, Single-Motor,
Error Switch Off
51 – I²t, Multi-Motor Operation,
Warning
52 – I²t, Single-Motor,
Warning
Agile
Operating Instructions
2

t- monitoring

2
t- monitoring)
2
t monitoring provides a further possibility for the user.
2
t- monitoring is a proven alternative to motor protection switch.
2
t monitoring mode can be selected by
/I )² as shown in the figure.
act n
The I²t capacity of the motor is monitored with rat-
ed values from the active dataset.
If the fixed threshold values exceed 100%
(120% ), the drive switches off with fault
stator
"F0401" in the active dataset.
The I²t capacity of the motors regarding their relat-
ed ratings is monitored in each of the four data
sets. If the
Warning Limit Motor I
the warning message "A0200" is signaled from the
active data set.
The I²t capacity of the motor is monitored with rat-
ed values from the active dataset.
If the
Warning Limit Motor I
warning message "A0200" is signaled from the ac-
tive data set.
248
06/2013
Parameter descriptions
Operation Mode
Function
615 is reached,
2
t
615 is reached, the
2
t
571.
motor
Special functions