HBK DSE, Operating Manual

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67
DSE
WEB INTERFACE
Fine flow pre-act
Coarse flow
cutoff point
Fine flow
cutoff point
Target weight
Coarse flow pre-act
Fig. 7.18 Definition of cutoff point and pre-act
The coarse flow cutoff point must not be higher than the fine flow cutoff point. If you do
not need coarse flow, set the pre-act to 0, then only the fine flow will be used.
Lockout time: Once coarse flow is activated, comparison of the actual weight for
reaching the coarse flow cut-off point is disabled for the specified duration. The time
does not delay the filling process.
Especially when the fill material has pieces, it may happen that the first pieces that fall in
the container after coarse flow has started will generate peak loads that will already
cause the coarse flow cut-off point to be exceeded. You can prevent that with this set­
ting. Based on experience, the lockout time should be about 10 % of the coarse flow time.
Fine flow (phase) first (before coarse flow): The fine flow signal is activated for the set
time after the start or after taring and before the coarse flow for the set duration. You can
also use this additional fine flow time before the coarse flow, for example to prevent the
coarse flow causing excessive foaming in the liquid being filled.
Fine flow
Pre-act: For the fine flow cutoff point, you must subtract the pre-act value from the target
weight. Rule (see also Fig. 7.18):
Fine flow cutoff point = target weight – fine flow pre-act
The fine flow cutoff point is always above the coarse flow cutoff point. This entry is
required, otherwise you will not be able to start a process.
Lockout time: The time starts when the coarse flow cut-off point is reached. Comparison
of the actual weight for reaching the fine flow cut-off point is disabled for the specified
duration. The time does not delay the filling process.
When the coarse flow shuts off, settling processes may occur that will already cause the
fine flow cut-off point to be exceeded. You can prevent that with this setting. Based on
experience, the lockout time should be about 10 % of the fine flow time.