Siemens 1FT7 Series, Руководство по настройке

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1FT7 Synchronous Motors
Configuration Manual, (PFT7S) 01/2009, 6SN1197-0AD13-0BP2
203
Motor components
5
5.1 Thermal motor protection
A temperature-dependent resistor is integrated as temperature sensor to monitor the motor
temperature.
The sensor is evaluated in the inverter whose closed-loop control takes into account the
temperature characteristic of the motor winding. When a fault occurs, an appropriate
message is output at the drive converter. When the motor temperature increases, a
message "Alarm motor overtemperature" is output; this must be externally evaluated. If this
signal is ignored, the drive converter shuts down with the appropriate fault message after a
preset time period or when the motor limiting temperature or the shutdown temperature is
exceeded.
CAUTION
The integrated temperature sensor only protects the synchronous motors to a certain extent
against overloads
Shaft heights 36 and 48 up to 2 ∙ I
0 (60 K)
and speed ≠ 0
from shaft height 63: up to 3 ∙ I
0 (60 K)
and speed ≠ 0
For load applications that are critical from a thermal perspective, e.g. overload when the
motor is stationary or an overload of M
max
longer than 4 s, adequate protection is no longer
available. The "thermal motor model i
2
t monitoring" function must be activated in the
converter.
The temperature sensor is part of a SELV circuit, which can be destroyed if high voltage is
applied. The temperature sensor is designed so that the DIN/EN requirement for "protective
separation" is fulfilled.