Scale Parameters And Functions; Parameters And Functions - Siemens SIWAREX WP251 Manual

Scale parameters and functions

8.1

Parameters and functions

SIWAREX WP251 can be used as a non-automatic weighing instrument (NAWI), an
gravimetric filling instrument or an automatic catchweighing instrument. The appropriate
operating mode must be selected based on the requirements for the scale. For systems
requiring official calibration, contact with the responsible weights and measures office at an
early stage is recommended in order to define the correct operating mode and thus to
correctly assign all parameters in advance.
The differences between the individual operating modes arise for the most part due to legal
requirements related to calibration, which is why the operating mode (factory setting) can
be used for dosing and mixing of individual components with scales that cannot be
calibrated.
In this operating mode, the PLC sends a set point to SIWAREX and starts the dosing via a
command. WP251 then switches the coarse and fine signal and doses the desired quantity
to the scale or removes it from the scale (filling or removal mode). SIWAREX WP251 can
also empty the scale, if required. An emptying signal is then switched. This signal is either
switched based on a fixed time (emptying time) or when Limit 3 (emptying limit) is fallen
below. After emptying, the next dosing is started directly (continuous mode) or WP251 waits
for the next start command. Emptying can optionally be switched on or off for each operating
mode.
All parameters are divided into data records (DR). The data records are organized in steps
(tasks) to be implemented during commissioning or during the process. All data records are
always read or written as complete packets, and therefore it is not possible to read or write
individual parameters within a data record.
The scale functions governed by the parameters are also described in the parameter
description below.
First, the parameters of a given data record are displayed in a table. The detailed parameter
description for the parameters of this data record then follows.
When it receives new parameters, the SIWAREX module runs a validation check. In the
event of a parameter assignment error, the data record is not applied (not saved) by the
SIWAREX module and a data/operator error is reported.
SIWAREX WP251
Manual, 12/2015, A5E37203357A
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