ABB ACS850 - Page 119

Parameters 119
19.07 Zero speed delay Defines the delay for the zero speed delay function. The
function is useful in applications where a smooth and quick
restarting is essential. During the delay, the drive knows
accurately the rotor position.
Without Zero Speed Delay:
The drive receives a stop command and decelerates along
a ramp. When the motor actual speed falls below an internal
limit (called Zero Speed Limit), the speed controller is
switched off. The inverter modulation is stopped and the
motor coasts to standstill.
With Zero Speed Delay:
The drive receives a stop command and decelerates along a
ramp. When the actual motor speed falls below an internal
limit (called Zero Speed Limit), the zero speed delay function
activates. During the delay the function keeps the speed
controller live: the inverter modulates, motor is magnetised
and the drive is ready for a quick restart. Zero speed delay
can be used e.g. with the jogging function.
0 … 30000 ms Zero speed delay. 1 = 1 ms
19.08 Above speed lim Defines the supervision limit for the actual speed.
0 … 30000 rpm Actual speed supervision limit. 1 = 1 rpm
No. Name/Value Description FbEq
Speed controller switched off:
Motor coasts to stop.
19.06 Zero speed limit
Speed
Time
Speed controller remains
active. Motor is decelerated to
true zero speed.
19.06 Zero speed limit
Speed
Time
Delay