Cwi - Catchweighing Instrument/ Cw - Automatic Check Weigher - Emptying - Siemens SIMATIC ET 200SP Operating Instructions Manual

Parameter assignment/addressing
6.4 Operating modes
In contrast to the NAWI weighing operating mode, the logging of the dosed single weight is
written automatically to the log memory without an operator intervention.
Dosing in continuous operation is possible.
In practice, the dosing process may proceed as follows:
1. PLC sends set point (DR 20) and material parameters (DR 23) to the electronic weighing
system
2. PLC sends "Start" command (e.g. 1101) to the electronic weighing system
3. The electronic weighing system performs zero setting or tares (based on DR 25) (weighing
step 1)
4. Coarse/fine dosing phase starts (weighing step 2)
5. If configured and necessary, post-dosing occurs (DR 22) (weighing step 3)
6. Dosing result is automatically checked and logged (weighing step 4)
7. Scale is emptied, if necessary (based on DR 25) (weighing step 5)
8. The electronic weighing system jumps to weighing step 0 and waits for further commands
or jumps directly back to step 1 (continuous operation).
6.4.4.2

CWI - Catchweighing instrument/ CW - Automatic check weigher - Emptying

In CWI/CW mode, the electronic weighing system also allows a set point to be set, which the
dosing functionality of the electronic weighing system then automatically doses.
In CWI/CW mode, the electronic weighing system also allows a set point to be set, which the
dosing functionality of the electronic weighing system then automatically doses.
The dosing signals "Coarse flow/Fine flow" can be used to directly control the corresponding
dosing elements (e.g. valves). After the set point is reached, the electronic weighing system
automatically logs the dosed weight in the log memory and completes the weighing operation
autonomously.
In contrast to the NAWI weighing operating mode, the logging of the dosed single weight is
written automatically to the log memory without an operator intervention.
"Removal" means that the product to be weighed is dosed from the scale (for example, a silo
on load cells with discharge valves). In this case, the full scale is tared and the net weight
increases with decreasing gross weight. The "Dosing start" parameter in DR 25 should be set
to "Tare" for correct operation.
Dosing in continuous operation is possible.
In practice, the dosing process may proceed as follows:
1. Scale is filled with sufficient material.
2. PLC sends set point (DR 20) and material parameters (DR 23) to the electronic weighing
system
3. PLC sends "Start" command (e.g. 1101) to the electronic weighing system
4. The electronic weighing system tares (based on DR 25) (weighing step 1)
5. Coarse/fine dosing phase starts (weighing step 2)
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Technology module TM SIWAREX WP351 HF
Operating Instructions, 01/2020, A5E47521010-AA