
MFC/MFM - 41
english
Standard control operation
Autotune routine
A prerequisiste for the automatic adaptation of the controller to the conditions in
the system is that the typical pressure conditions pertain.
Initiate the Autotune routine by operating the binary input 1.
The Autotune routine runs automatically. During this operation, the green POWER
LED flashes.
ATTENTION!
NOTE
This is the operating mode in which the MFC finds itself after being switched on
and after a short initialization phase. In the LED group, only the green Power LED
lights.
The flow rate is controlled to the setpoint with high sensitivity. Disturbances such
as those resulting from pressure variations are rapidly corrected by suitable
adjustment to the aperture of the control valve.
In this mode, the setpoint is set via the analog input (standard signal input) or the
field bus, depending on the version of the device.
The controller parameters are set such that changes in the process value or
distrubances are corrected as fast as possible without significant overswing being
caused.
When the driving signal of the control valve approaches the
100 % limit, the LIMIT (y) LED lights. The cause is usually that
the pressure difference over the MFC is too small, e.g. because
the pressure supply is insufficient or the filter is heavily
contaminated. This can lead to non-achievement of the setpoint
and an enduring positive actuating signal (w-x). To enable an
external reaction to be made to this situation, a relay output is
actuated in addition.
While the Autotune routine runs, the MFC does not control. The control valve is
driven according to an internally specified scheme. This leads to flow changes,
whereby some of the control parameters are adapted to the conditions pertaining
in the system. At the end of the Autotune routine, these parameters are stored in
the non-volatile memory of the device.
After completion of the Autotune routine, the MFC returns to the previous
operating mode.
Observe the following points while the Autotune routine runs:
Various changes in flow occur.
The power supply of the MFC must not be switched off.
The supply pressure should be kept constant.
Operating modes of the MFC
Содержание 8006 Series
Страница 26: ...26 MFC MFM english Fig Type 8712 8702 MASS FLOW CMOSens Fig Type 8713 8703 MASS FLOW CMOSens ...
Страница 27: ...MFC MFM 27 english Fig Type 8716 8706 MASS FLOW INLINE with standard sensor body ...
Страница 74: ...74 MFC MFM deutsch Bild Typ 8712 8702 MASS FLOW CMOSens Bild Typ 8713 8703 MASS FLOW CMOSens ...
Страница 75: ...MFC MFM 75 deutsch Bild Typ 8716 8706 MASS FLOW INLINE mit Standard Sensorblock ...
Страница 122: ...122 MFC MFM français Figure Type 8712 8702 MASS FLOW CMOSens Figure Typ 8713 8703 MASS FLOW CMOSens ...
Страница 123: ...MFC MFM 123 français Figure Type 8716 8706 MASS FLOW INLINE avec corps de capteur standard ...
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