Burkert Type 8635 - Manual (Page 60)

58 - 8635
O
PERATING AND
C
ONTROLLER
F
UNCTIONS
TUNE-PWM - Readjustment of minimum PWM pulse-duty factor for driving the piezoelectric
valves integrated in the SIDE Control
The AUTOTUNE function determines automatically the required PWM-PDF for driving the piezoelectric
valves integrated in the SIDE Control. These values may deviate from the optimum because of
unfavourable frictional behaviour of the actuator. With
TUNE-PWM, you can reajust it such that the
lowest possible speed results for both directions of movement.
TUNE-AIR - Adaptation of the opening and closing times of the process valve
The required maximum air flow capacity of the internal positioning system depends on the volume of the
actuator. Ideal control behaviour of the positioner is obtained with an air flow capacity that leads to an
opening or closing time of the armature of 1 ... 2 s. For this reason, the SIDE Control is equipped with a
throttle screw to vary the maximum air flow capacity of the internal positioning system. The position of
the throttle screw is to be seen in the chapter
System Description / Structure of the SIDE Control. The
adjustment of this throttle screw is made by means of TUNE-AIR , whereby the corresponding times are
determined by cyclic opening and closing of the valve and displayed.
NOTE The function TUNE-PWM must be executed after AUTOTUNE!
NOTE The function TUNE-AIR must be executed after AUTOTUNE!
ATTENTION!
To avoid cause faulty adaptation of the controller, be sure to execute X.TUNE at the
supply pressure (= pneumatic auxiliary energy) that will exist in later operation.
The function X.TUNE should be executed preferably without operating medium
pressure to exclude disturbances from forces resulting from flow.
END - Quitting the main menu
➔ To quit the main menu, select the menu item END with the arrow keys .
On the right of the display, the software version is shown (END XX). After pressing the MANUAL/
AUTOMATIC key, the message EEPROM appears on the display for ca. 3 ... 5 s while the changes
are being stored. Afterwards, the device is back in the mode in which it was before switching over to
the main menu (MANUAL or AUTOMATIC).