Actual signals and parameters
Parameters in the Long parameter mode
Defines the acceleration time 1, that is the time required for the speed to
change from zero to the speed defined by parameter 2008 MAXIMUM FREQ.
- If the speed reference increases faster than the set acceleration rate, the
motor speed follows the acceleration rate.
- If the speed reference increases slower than the set acceleration rate, the
motor speed follows the reference signal.
- If the acceleration time is set too short, the drive automatically prolongs the
acceleration in order not to exceed the drive operating limits.
Actual acceleration time depends on parameter 2204 RAMP SHAPE 1
setting.
Defines the deceleration time 1, that is the time required for the speed to
change from the value defined by parameter 2008 MAXIMUM FREQ to zero.
- If the speed reference decreases slower than the set deceleration rate, the
motor speed follows the reference signal.
- If the reference changes faster than the set deceleration rate, the motor
speed follows the deceleration rate.
- If the deceleration time is set too short, the drive automatically prolongs the
deceleration in order not to exceed drive operating limits.
If a short deceleration time is needed for a high inertia application, the drive
should be equipped with a brake resistor.
Actual deceleration time depends on parameter 2204 RAMP SHAPE 1
setting.
Selects the shape of the acceleration/deceleration ramp 1. The function is
deactivated during emergency stop (2109 EMERG STOP SEL) and jogging
(1010 JOGGING SEL).
0.0 = LINEAR
0.0…1000.0 s
0.0 s: Linear ramp. Suitable for steady acceleration or deceleration and for
slow ramps.
0.1…1000.0 s: S-curve ramp. S-curve ramps are ideal for conveyors carrying
fragile loads, or other applications where a smooth transition is required
when changing from one speed to another. The S-curve consists of
symmetrical curves at both ends of the ramp and a linear part in between.
A rule of thumb
Speed
Linear ramp: Par. 2204 = 0 s
A suitable relation between the
Max
ramp shape time and the
acceleration ramp time is 1/5.
S-curve ramp:
Par. 2204 > 0 s
t
Par. 2202 Par. 2204