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SCAIME Manual : NU-eNod4B-ETH-E-236708-D.docx
Belt weigh feeder operation
The
weigh feeder
is used to deliver an accurate mass flow rate of materials. In most applications, materials are provided by
an adjustable mechanical shear gate, which fixes the correct material bed depth for a given particle size.
The feed rate is then maintained adjusting the speed of the belt. However, in some cases the belt speed is constant with rate
control done by a pre-feeding device.
The system consists of three components: weight and speed sensing, integration and control, and the mechanical conveying
system.
Using the belt load and the belt speed signals, small incremental totals of weight per time are measured by
eNod4
which
calculates the flow rate. The measured flowrate is compared to the set point flow rate and the on-board PID controller makes
necessary corrections to the belt speed or materials feed.
11.2
Totalization cycle description
11.2.1
Cycle options
Cycle options define
eNod4
device functioning
Batch mode
If batch mode option is activated,
eNod4
will automatically stop dosing when the total weight will have reached batch target
values (Batch set point minus Inflight weight value), the scale material flow stops automatically.
The batch target value consists of two variables, the
main
weight to totalize
in
weight unit
x 1000 and the
complementary
weight to totalize
in
weight unit
.
Inflight weight
value is expressed only in
weight unit
.
Clear totalization
If
cleared totalization at starting of new cycle option
is activated,
eNod4
reinitializes total value. The main variable
weight to
totalize
in
weight unit
x 1000 and the
complementary weight to totalize
in
weight unit
are reset to zero.
PID Activation
It is possible to assign
eNod4
current or voltage analog output to extraction command (Setting
to flow rate control output
).
