Rockwell powerflex 700h, Руководство по программированию

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Application Notes B-5
[Motor NP FLA] is multiplied by [Motor OL Factor] to select the rated
current for the motor thermal overload. This can be used to raise or lower
the level of current that will cause the motor thermal overload to trip. The
effective overload factor is a combination of [Motor OL Hertz] and [Motor
OL Factor].
Overspeed
Overspeed Limit is a user programmable value that allows operation at
maximum speed, but also provides an “overspeed band” that will allow a
speed regulator such as slip compensation to increase the output frequency
above maximum speed in order to maintain maximum motor speed.
The figure below illustrates a typical Custom V/Hz profile. Minimum Speed
is entered in Hertz and determines the lower speed reference limit during
normal operation. Maximum Speed is entered in Hertz and determines the
upper speed reference limit. The two “Speed” parameters only limit the
speed reference and not the output frequency.
The actual output frequency at maximum speed reference is the sum of the
speed reference plus “speed adder” components from functions such as slip
compensation.
Changing Overload Factor
0 10 20 30 40 50 60 70 80 90 100
% of Base Speed
Contin
uous Rating
OL % = 1.20
OL % = 1.00
OL % = 0.80
0
20
40
60
80
100
120
140