Configuration Manual Synchronous Motors 1FK7 - Siemens ...

Motor Components (Options) 4
4.1 Thermal motor protection
A temperature-dependent resistor is integrated as temperature sensor to monitor the motor
temperature.
Table 4-1: Features and technical data
Type KTY 84
Resistance when cold (20°C) approx. 580 Ohm
Resistance when hot (100°C) approx. 1000 Ohm
Connection via signal cable
The resistance of the KTY 84 thermistor changes proportionally to the winding temperature
change.
The temperature signal is sensed and evaluated in the drive converter whose closed-loop
control takes into account the temperature characteristic of the motor resistances.
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 not observed, the drive converter shuts down with the
appropriate fault message when the motor limiting temperature or the shutdown temperature
is exceeded.
Warning
If the user carries-out an additional high-voltage test, then the ends of the temperature sensor
cables must be short-circuited before the test is carried-out!
If the test voltage is connected to a temperature sensor terminal, then it will be destroyed.
The polarity must be carefully observed.
The temperature sensor is designed so that the DIN/EN requirement for "protective separation"
is fulfilled.
1FK7 Synchronous Motors
Configuration Manual (PFK7), 10/2005 Edition, 6SN1197-0AD06-0BP1 4-1