Duplomatic EWM-2SS-DAD/22E-PN, Руководство для стартапов

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Start-up Manual 89475/119 ETM
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Duplomatic MS S.p.A. All rights reserved.
Control bits via fieldbus:
It is possible to activate drift compensation as well as high accurate positioning by the fieldbus.
This can be accomplished by using the following control bits:
DC_ACTIVE : General activation of the drift compensation and high accurate positioning
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.
DC_FREEZE : Freezing of the static drift compensation value.
DC_F_POS : Activation of the high accurate positioning (dynamic drift compensation).
Typical setup
Valve pressure gain: 2,5%
the activation point has to be set to 3
… 5 % (DC:AV 300… 500).
Valve hysteresis: 0,5%
the deactivation point has to be set to 0,7… 1,0 % (DC:DV 70… 100).
The lower the value the better the accuracy.
DC:CR should be equal to DC:AV. Limiting the control range of the integrator is necessary to avoid
long settlement durations.
The optimum integrator time has to be determined experimentally. Starting with higher values is
recommended.
The integration time usually has to be determined by experiments. For this it is recommended to
start with a long time (1500 ms) and to reduce it gradually. If overshooting or limit cycling occurs,
the time setting has become too small.
DC (drift compensation)
Command Parameter Unit Group
DC_1:I x
DC_1:AV x
DC_1:DV
x
DC_1:CR x
DC_2:I x
DC_2:AV x
DC_2:DV
x
DC_2:CR x
x= 0… 2000
x= 0… 2000
x= 0… 10 00
x= 0… 500
x= 0… 2000
x= 0… 2000
x= 0… 1000
x= 0… 500
ms
0.01 %
0.01 %
0.01 %
ms
0.01 %
0.01 %
0.01 %
EXTRA
DC:I This parameter is used to define the integrator time. The lower this value the faster
the compensation. Low values will result in
“ limit cycling “ .
DC:AV This parameter is used to define the activation point (activation value).
The DC function is completely deactivated in case of DC:AV = 0.
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The static drift compensation should always be carried out at first, to adjust the zero point and the freezing of this
value. Only by this it is possible to avoid or minimise overshooting of the target position.