NORD Drivesystems BU0210 - Manual (Page 46)

SK 2x5E with "PosiCon Functionality"
46 Subject to technical amendments BU 0210 GB
6.3 Settings for slave ramp time and maximum frequency
In order for the slave to be able to perform the control, the ramp times should be selected somewhat smaller
than for the master and the maximum frequency should be selected somewhat higher.
Slave device settings:
P102
Slave
= 0.5 ... 0.95 * P102
Master
P103
Slave
= 0.5 ... 0.95 * P103
Master
P105
Slave
= 1.05 ... 1.5 * P105
Master
P410
Slave
= P104
Master
P411
Slave
= P105
Master
For the slave, frequency addition (instead of setpoint frequency) is set in parameter P546 "Function Bus -
Setpoint Value 1". Otherwise the problem would occur that the for the slave the maximum frequency could only
be set slightly higher than for the master in order prevent the specification from being falsified too much.
However, this removes the possibility for the slave drive to "catch up" at speeds close to the maximum
frequency.
6.4 Setting the speed and position controls
The speed and position controls are set as would be the case if there was no synchronous operation.
Therefore, if possible, the speed control should first be set in parameter P300 "Servo Mode", then the position
control in parameter P600 "Position Control" and then the synchronisation control should be commissioned.
The dynamic results are improved, the more sharply the controls can be set. From experience however, the
position control functions better if the I component in the speed control is not too large. The speed control
should therefore be set for a slight overshoot. This results in a P component which is as high as possible (until
noises occur at low speeds), and a rather moderate I- component. The setting of the torque limits and the
selected ramps must be made so that the drive can always follow the ramp.
6.5 Taking a speed ratio between master and slave into account
A speed ratio between the master and the slave can be taken into account via the parameters P607 "Speed
Ratio" and P608 "Reduction Ratio". The speed ratio is entered into the values of the unused encoder.
Therefore in general, for absolute encoders (P607 [02] and P608 [02]).
N
Slave
= P607 [xx] / P608 [xx] * N
Master
P105
Slave
= P607 [xx] / P608 [xx] * P105
Master
* 1.05 ... 1,5
P410
Slave
= P104
Master
P411
Slave
= P105
Master
There is also the possibility of changing the speed ratio between the master and the slave via an analog input
of the optional IO extension module. The speed ratio can then be continuously varied between -200% and a
maximum of 200% of the master speed. The analog input can be scaled via the parameters P402 and P403
(see Manual BU 0200) according to requirements. For negative values there is a change of direction of
rotation. The function of the analog inputs (P400) should be set to Function 25 = Speed Ratio Gearing. It is
possible to adjust the speed ratio "online", however, it should be noted that the "Position slip error" in
parameter P630 "Position Slip Error" can take on considerably larger values during the adaptation than for
normal synchronous operation, as acceleration or braking to the new speed must be performed.