
The Design Weight is important, because it is used for automatically setting the hopper
parameters and for scaling the Weight analog output.
The
Max Batch Wt
is important, because it is used for automatically setting the batch
parameters and for scaling the Setpoint analog input and the Batch Total analog output.
Bach Parameters
The batch parameters deal with the batching process. They are critical for performance
and accuracy.
Fast Feed Spd
Determines the speed demand value for the feeding device during Fast Feed. Default is
80%. Upper limit is determined by behavior when turning Fast Feed off. Vibratory feeders
are notorious for mass-flowing when turned off from a high amplitude vibration.
If you are not using Fine Feed, set
Fast Feed Spd
to the lowest value that produces the
largest batch you will use the in time available. When fine feed is used, the rule of thumb
is to divide the available time equally between the fast feed and fine feed.
Fine Feed Spd
Determines the speed demand value for the feeding device during Fine Feed. Default is
20%. The slower the fine feed the better the batch accuracy, but also the longer the
batch time. For VFD drives, a very low fine feed speed may cause the VFD to overheat
or the feeder to stall. For vibratory feeders, there is a tendency for the feedrate to
asymptotically go to zero at low fine feed speed. Make sure the feeder can feed at the
fine feed setting for a long time.
Fine Feed Wt
The controller changes from Fast Feed to Fine Feed, when there is
Fine Feed Wt
left to
feed to reach the batch setpoint. A value of Zero eliminates fine feed altogether. The
Fine
Feed Wt
is automatically adjusted if a non-zero value is used for
Fine Feed Tm
, see
below. The value is critical. Too much
Fine Feed Wt
will result in unnecessarily slow
batching. To little will result in poor batch accuracy. It is highly recommended to let the
MC³ adjust this parameter automatically.
A common scenario is zig-zagging, which happens if the
Fine Feed Wt
is set too low. It is
characterized by interaction with the Preact. On the first batch, the fine feed is skipped,
and the Preact is adjusted up, because of high batch total. On the next batch, fine feed
will occur (because of the adjusted Preact), the batch total will be low, and the Preact is
adjusted down. This will repeat every other batch. TO correct this, used timed Fine Feed
weight (below) or increase the
Fine Feed Wt
parameter.
Fine Feed Tm
With a non-zero value, the MC³ will measure the fine feed time every batch. If it is shorter
than
Fine Feed Tm
, the
Fine Feed Wt
is adjusted up, and vice versa. With a value of
zero, the function is disabled, and the
Fine Feed Wt
is not adjusted. Use a value of 30 –
50 % of the available batch time.
Fine Feed Adj
Determines aggressiveness of the Fine Feed adjustment, when timed Fine Feed is used.
The Default value of 100% usually works fine, but if the Fine Feed Weight is wobbling
between batches, decrease this value. If it takes a long time for the fine feed time to
reach the setting in
Fine Feed Tm
, increase
Fine Feed Adj
.
Curr Preact
The feeder switches off when the batch total equals the setpoint plus the Preact. The
value is normally negative. When the final batch total is available, after the Stable Check,
Preact is typically adjusted. If the batch total is greater than the setpoint, Preact is
35.00.EX O&M Manual
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