EMR-5000
IM02602012E
In the Thermal Replica Model Trip Curves with and without RTD, the unmarked lines are the thermal limit curves and
the marked lines are the trip curves. From the curve without RTD, it can be seen that one can change the thermal
current threshold to shift the upper portion of the trip curve right to allow the motor to run at a higher overload condition
than is specified with the service factor. From the curve with RTD, it can be seen that the stator RTD pushes the
effective thermal current threshold to 2.55 FLA on the thermal limit curve (unmarked line). The marked line is the trip
curve with 80% thermal capacity trip threshold, so actual effective thermal current threshold for the trip curve is about
2.05 FLA. Although in this case, the thermal current threshold is set to 1.50 FLA, it is effectively raised to a higher level
with the stator RTD. Keep in mind that thermal limit and trip curves shown are based on the example above. They will
vary with other sets of the settings.
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