Arcteq AQ-M255, Инструкция по эксплуатации

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Figure. 5.3.23 - 124. Example of thermal limit curves in a motor.
From motor thermal limit curves –if available– one can see the time constants for overloading as well as
the safe stall times for hot and cold situations. Additionally, the cooling time constant must be checked
from the motor datasheet or alternatively measured. From the image above one can estimate the safe
stall time in cold situations to be approximately 80 seconds, and in hot situation approximately 67
seconds. When the thermal limit curves are available, the operation of the thermal replica can be set
very accurately for both overloading and stall conditions.
The cooling time constant as presented in the previous example is very crucial in the case of variable
duty cycle motor applications. If the motor is continuously running with a constant load, the cooling
time constant is not that significant and can be estimated to be e.g. two to three times longer than the
heating time constant.
A AQ Q-M255 -M255
Instruction manual
Version: 2.06
232 © Arcteq Relays Ltd
IM00020