DOSAGE
33
EXAMPLE:
FORMULA:
dosagE 01
In the suggested example, the instrument will execute an automatic dosage as first activity, and then a
manual dosage, then a timer activity, and then, the total unloading of the silo.
The execution order of the activities depends on the order in which these are entered when programming
the formula: the first entered activity will be the first executed one, etc.
6.2
“Automatic dosage” type of an activities
a)
Description
This activity has the purpose to automatically dose a product:
-
This activity automatically starts at the end of the previous one.
-
Once the dosage is started the instrument tares the weight on the scale and enables the fast dosage
output and the product one: the dosage starts at the maximum speed.
-
When the weight reaches the TARGET TO BE DOSED - SLOW DOSAGE WEIGHT - MATERIAL WEIGHT
IN FLIGHT threshold, the approximate dosage output disables and the dosage continues in fine
mode.
-
The dosage ends, with subsequent disabling of the output relative to the linked output, in the
moment in which the TARGET minus the MATERIAL WEIGHT IN FLIGHT is reached.
-
After this a wait time starts equal to the Time for material falling down (
) in which one
presumes that material still falls on the scale and the TARGET is reached.
-
Once the wait time is finished:
i.
If the instrument is enabled, the checks start on the dosage result: if the weight of the dosed
material is not within the set tolerance, the "TOLERANCE ERROR" error is signalled, and the
error output (default = OUT3) is enabled.
Now the operator can remove the exceeding weight or add the missing weight; in this phase it is
possible to use the message which appears (WEIGH OK if within the tolerance, or TOLERANCE
ERROR if out of tolerance).
By pressing for an instant the external INPUT 1 or the START button, one exits the error status: the
weight now present will be considered valid and therefore accumulated in the formula production
and in the general total.
ii.
The data of the executed dosage is automatically stored and transmitted through the serial
line for the printing or the storage on PC/PLC.
-
A wait time starts equal to the DATA READING TIME (
) in order to allow the reading of the
activity data; the instrument waits for this time before passing to the following phase.
b)
Phase of the activity shown on the display
R1 and R2 relay (dosage and speed relays) are enabled: the process then starts at maximum speed.
The status bar message on the display is:
1.
AUTOMATIC FAST DOSAGE
indicates that the material is being dosed at the maximum speed; this
AUTOMATIC
DOSAGE
MANUAL
DOSAGE
TIMER
TOTAL UNLOADING
Activity 1
Activity 2
Activity 3
Activity 4
