Lenze I95AE240F User Manual

13.9.1.2 Speed-dependent evaluaon of the motor current
WARNING!
Fire hazard by overheang of the self-venlated standard motor
P
ossible consequence: destrucon of system parts
▶
Protect self-venlated standard motors especially at low speeds by sucient cooling or
from impermissibly high motor currents. Carry out a speed-dependent evaluaon of the
permissible motor current.
WARNING!
Fire hazard by overheang of PM synchronous motors
P
ossible consequence: destrucon of system parts
▶
Please check for every individual case which r.m.s. value can be used to permanently oper-
ate the motor at standsll. In case of some motors, a derang I1/In < 100 % is required
when n1/nn = 0 %. This serves to prevent an overload of individual motor phases as their
power loss doubles with connuous DC current load. (It is called DC current load as the eld
frequency amounts to 0 Hz at standsll.)
When you select a Lenze motor from the catalogue and transfer its parameters
in
to the i700 servo inverter a typical characterisc is automacally set for the
selected motor. A deviang parameterisaon is only required if the motor is
operated in ambient condions which demand a general derang. Example: use
in site altudes > 1000 m. In case of motors of other manufacturers, the operat-
ing points have to be parameterised based on the data sheet informaon.
By
selecng a characterisc, the permissible motor current is evaluated depending on speed
for calculang the thermal motor ulisaon. For this purpose, up to four operang points on
the S1 characterisc of a motor can be used.
•
The S1 characterisc can be found in the technical data sheet/catalogue of the respecve
motor.
•
The representaon in the objects /characterisc is carried out as relave values with refer-
ence to rated values.
The speed-dependent evaluaon of the permissible motor current can actually be switched
o by parameterising all 8 characterisc points to "100 %".
Operang points
① Standsll n01-I01 For motors, this operang point is oen descri-
bed with the no-Io v
alues.
② Reference point n02-I02 If the value falls below the speed n02, a derat-
ing in the current is required because:
•
the motor cooling of self-venlated motors
deteriorates considerably.
•
a DC current load causes an increased power
loss in a winding.
•
For motors, this operang point is also
described with the no-Io values.
③ Rated point (n03=nN)-(I03=IN) Rated values of the motor are the reference for
all operang points of the i
2
xt monitoring.
④ Field weakening n04-I04 This operang point should be parameterised
irrespecve of the use in the current applica-
on.
Conguring the motor control
Mot
or protecon
Motor overload monitoring (i²*t)
268

Lenze I95AE240F Specifications

General

Brand	Lenze
Model	I95AE240F
Category	Inverter
Language	English