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Can ATV process avoid tripping in drive overtemperature fault by reducing automatically the speed when drive thermal state is quite high?

Lets calrify the details regarding such functionality at first :
1. Inverter temperature go hand in hand with inverter losses. The losses depends on several factors, but mainly on motor current and switching frequency.
2. Reduction in the speed can work only in case of quadratic or linear torque (pumps, fand, compressores, etc.). In case of constant torque application, the current will not drop at lower speed, so reduction in speed does not lead to lowering the losses and eventually drive will trip. 
3. With reducing the switching frequency the losses will be lower, but such an option is not automatic. Switching frequency cannot be modified in running state or switched to other value by digital signal.
4. If the size of ATV is selected properly acording to motor data and aplication cycle, and with respect to environmental conditions, the drive should never reach the overtemperature. But I understand if size of ATV is not enough, this function could prolong operation before the overtemerature fault or avoid the fault entirely.
What you can do (speaking about ATV process) is here in 2 possibilities:
a) to assign relay output to "drive thermal state reached" and wire this ralay output to one of digital input assigned to preset speed for example. Threshold for "drive thermal state reached" is done using THA drive thermal state warning.
b) to use drive overload monitoring (in menu Error/warnign mngmt) and define OHL=fallaback speed and THA (thermal state warnign)=xx %. Do no forget to configure fallback speed LFF.
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