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SCAIME Manual : NU-eNod4B-ETH-E-236708-D.docx
Conveyor total length
, if user does not know
pulses factor speed sensor (pulses/meter),
he has to fill this
parameter and
eNod4
allows estimating
pulses factor
. At end of calibration the current belt speed must match
the real speed.
Number of revolutions,
for auto-calculation of
pulses factor
or
conveyor total length
, user must fill this
parameter with correct value (effective number of revolutions to be realized during procedure). It is
recommended to set and to achieve a maximum number of revolutions to improve result accuracy.
Procedure of auto-calculation (
pulses factor
or
total length
) is as following:
Stop the conveyor and make sure it is empty
Mark the belt (for reference point)
Start the conveyor
Send corresponding “
Init calibration
” command at marked point
Count real number of belt revolutions handled
Send corresponding “
End calibration
” command at marked point and when specified number of
revolutions is done.
Check and compare updated value of
pulses factor
or
conveyor total length
.
Note
: See functional commands section about commands list.
11.3.2
Static weight calibration
Static weight calibration must be performed when the conveyor is in stop state
. eNod4
device allows several methods of
static weight calibration. These methods and procedures are described in specific calibration and scale adjustment section.
Refer to it for more details.
11.3.3
Material Test (Dynamic weight calibration or correction factor)
The Material Test can only be performed once a static weight calibration has been completed and once the belt speed sensor
has been installed and calibrated.
The belt scale allows for two calibration methods. Static weight calibration is the easiest method and is a combination of test
weights applied to each weigh idler, belt spacing and speed calibration. The second optional calibration method is a Material
Test calibration in which a known amount of test material is fed on the moving belt scale. Then, user must check the amount
of test material with a measurement instrument and apply a correction factor to make at next batch
eNod4
displayed total
weight matches the test material weight.
11.4
Calibration of flow rate
So that
eNod4
can carry out an expected flow rate dosing in the best conditions possible, the flow rate output control
calibration is required. This also applies when
eNod4
is used both as
belt scale
or
belt weigh feeder
.
From this calibration will depend the accuracy of the flow rate obtained and on the actuation time delay, if a PID
regulator
controls it. This calibration is carried out in minimum two segments by the variable
segments number for the calibration
curve of flow rate
.
In case the extraction device has a nonlinear response, it is recommended to define maximum segments
for the flow rate calibration.
If the control of extraction device is directly provided by
eNod4
through a control analog output in
current
or
voltage
, the
current
or
voltage
analog output of
eNod4
must be allocated to “
level on request”
function
.
For each calibration point of the variable
control output value,
read the appropriate average flow rate. Then provide each of
the
Calibration of control output point n / analog output
and
Calibration of flow rate point n
matching with
control output
value.
Validate the flow rate calibration by
calibration of flow rate
control.
Allocate in the end the
current
or
voltage
analog output of
eNod4
to “
flow rate control output”
function
.
11.5
Totalization
eNod4
realizes totalization function continuously while belt loading is greater than
minimum load to totalize
even if no batch
cycle is in progress.
The
totalization result
is composed of two parts, the
main part in
weight unit
x 1000 and the second one
complementary
in
weight unit
.
In
batch mode
and when
cleared totalization
at
starting new cycle
option is activated, this totalization result is set to zero at
each cycle start.
There are two others levels of totalization expressed only in
weight unit
x 1000 (
Great total
and
General total
).
Each totalization result can be independently set to zero. The data of these totalizers is being permanently backed up after
modification.
If one of these 4 outputs is allocated to an external totalizer, a pulse is sent when the value totalized increases by a multiple
value of the parameter
weight quantity per pulse on logical output.
