Compensate hysteresis of Hydraulic valve in IQAN?

Niklas 4 years ago in IQANdesign updated by Ulrik Zakariasson (Software development) 3 years ago 2


Is there a easy way to compensate hysteresis of a hydraulic directional control valve with IQAN. Example: we need 50mA more to increase flow to a certain level than decreasing down to it from a higher standpoint.



In IQAN there's not possible to adjust the PWM amplitude on the standard current output (for e.g. the transmission module XT2 with superimposed dither it's possible).

The current amplitude will depend on the load, duty cycle and the frequency. Since the load is firm and the duty cycle will depend on the load (the regulating current) there's only frequency that's possible adjust.

For Parkers L90 valve we recommend 100-125 Hz frequency but if you have for example a manual lever the fiction could be higher (=more hysteresis) and hence you would need to lower the frequency a little to compensate for that extra friction. Try to lower the frequency to 80 Hz (lower than 70 Hz can result in machine vibrations and noise) and check if it gives you the improvement of higher current amplitude. It should result in lower hysteresis on the valve.