KEB COMBIVERT F5-A, Applications Manual, Page: 383 / 552

Protective functions
© KEB, 2012-10 COMBIVERT F5-A, -E, -H Page 7.13 - 9
7
PTC
A temperature sensor integrated into the motor winding is connected to the terminals T1/T2 of the inverter. If a
resistance of 1650...4000 Ohm is exceeded, motor overtemperature is detected. If the resistance drops below
750...1650 Ohm, the state motor overtemperature is reset.
Thermal contact (NC contact)
A thermal contact integrated into the motor winding is connected to the terminals T1/T2 of the inverter. The
opened state is recognised as motor overtemperature.
KTY
In Pn.62 "dOH warning level", a temperature in the range of 0...200 °C is defined which, when exceeded,
causes a motor overtemperature message.
The current temperature is displayed in ru.46 "motor temperature". With a standard power circuit Pn.62 has no
function. In the motor temperature display ru.46 only T1-T2 closed or T1-T2 open is displayed.
7.13.1.10 Software motor protection
Additionally to the monitoring of the motor with a temperature sensor, a motor protection can be realised also
by monitoring the motor current.
The monitoring function is implemented differently for asynchronous and synchronous motors.
Emulation of an electronic motor protection relay
The functional description (times, current level, etc.) are found in chapter 7.13.9 "electronic motor protection".
The response to the triggering of the electronic motor protection relay can be defined with Pn.14 "warning
OH2 stop. mode". Dependent on the programming, the inverter raises "30: ERROR! Motor protection function"
(E.dOH2) or "97: ABN. Motor protection function" (A.OH2).
After the cooling period, the error or the malfunction, respectively, can be reset.
Motor current monitoring for servo drives
The functional description (times, current level, etc.) are found in chapter 7.13.9 "electronic motor protection".
When the protection function triggers, the error "30: ERROR! Motor protection function" (E.dOH) is triggered.
The error is resettable after approximately 100 ms.
A level of 0...100 % (100% = triggering time of the error) can be adjusted with Pn.15 "OH2 warning level" which
generates a pre-warning.
The response to the pre-warning is set with Pn.14 "Motor protection function response". With this, an abnormal
stopping can be executed before the drive raises an error. During the abnormal stopping, the inverter has status
"97: ABN. Motor protection function" (A.OH2). The switching condition "10: Motor protection relay function" is
met.