For physical reasons electromagnetic brakes take a certain amount of time before responding. As a
result load sagging may occur in lifting gear applications because there is a delay before brake ac-
tion applies to the load as well.
This kind of delayed action can be taken into account by providing a suitable setting of parameter
P107 (brake control).
During the brake reaction time which is adjustable as required the frequency inverter will supply the
absolute minimum frequency set in P505. As a result the motor will not start up against the brake
and loads will not sag when the motor stops.
For this aspect see also the >Lifting time< parameter P114.
Notes: We recommend that (especially with hoisting gear) an internal relay be used for
electromagnetic brake control (P434/441 function 1, external brake). Besides
do not select an absolute minimum frequency less than 2.0 Hz (P505).
Note: After a brake release time has been set (P107 / P114), the brake will not be controlled until
at least ¼ of the rated magnetization current (P209) is flowing. The static boost will be taken
into account accordingly if the values are < 100%.
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