gefran ADV200-HC Instruction Manual page 19

Power Speed Up
The purpose of this function is to obtain the maximum possible speed of vertical movement based on the
load.
In case of light loads the motor works in the defluxing zone with consequent reduction of available torque.
There are different conditions depending on the direction (up or down). The more critical direction is down,
where the load must be braked to stop it.
Overspeed up
A rise in the speed reference beyond the work limit at constant torque may lead to a condition where available
motor torque is insufficient to move the load. This automatically causes a decrease in motor speed and an
increase in available torque. The system is therefore stable.
Overspeed down
A rise in the speed reference beyond the work limit at constant torque may lead to a condition where available
motor torque is insufficient to support the load. The motor drags, speed increases further where available
torque is still insufficient. The system is therefore unstable.
The Power Speed Up function must therefore avoid an excessive speed that is incompatible with the load
moved.
The control algorithm monitors available power and the power absorbed by the motor in the various phases
of movement. Via regulator P, it reduces motor acceleration value and gradually brings it to zero when
absorbed power reaches the set limit, thereby defining the work speed.
ADV200-HC Manual Page 19 of 55