Dr 22 - Trailing Weight - Siemens SIWAREX FTA Device Manual

5.15.2 DR 22 - Trailing Weight

The trailing weight should correspond with the amount to add to the amount of the
dosage from the coarse- and fine-signal after switching the fine signal off. This
means, the fine shut-off point can be calculated as follows:
Fine shut-off point = Set value – trailing weight
The proportional controllers can offset the fine shut-off point by determining the
new trailing weight.
5.15.3 DR 22 - Fine Weight
The fine weight entry should correspond with the material amount that was dosed
during the fine signal (after switching off the coarse signal until switching off the
fine signal). The defined value should be measured so that the material flow can be
stabilised by the time that the fine signal is switched off. This means, the coarse
shut-off point can be calculated as follows:
coarse shut-off point = Set value – Fine weight – Trailing weight
The proportional controllers can offset the rough shut-off point by determining the
new trailing weight.
5.15.4 DR 22 - Shut-off correction value
The shut-off correction value for the fine signal changes the fine shut-off point by
the defined entry. The resulting fine shut-off point offset can be used to deliberately
achieve an over-dosage or under-dosage. This can be used to compensate for
interfering forces such as pressure, vacuum, etc., occurring with the dosage.
5.15.5 DR 22 - Timer pre-dosing
If an output has been defined for the pre-dosing
Outputs 1, 2, 3, 4, 5, 6, 7,
procedure start and which controls a coarse pre-dosing that depends on time can
be defined with this parameter. This can be used if another dosing step (coarse 1,
coarse 2) is required in addition to coarse and fine steps for example.
5.15.6 DR 22 –Tolerance TO1, Tolerance TU1, Tolerance TO2, Tolerance TU2
4 values can be defined for the tolerance evaluation. Based on this value, the
results of the automatic operation are tested with reference to the set value.
The values are defined so that TO2 > TO1 and TU2 > TU1.
This way, 2 tolerance bands are defined around the set value.
SIWAREX FTA
(see DR 7 - Definition of the Digital
8) then the time that is started with the weighing
Weighing Functions
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