Configuration Of Potentiometer Input; Activation Of Embedded Linearisations - PR electronics 5343B Bedienungsanleitung

Configuration of potentiometer input

In an Ohmic level sensor the resistance value changes when a magnetic floater
activates the reed contacts in the sensor. This means that it is usually not
possible to make use of the entire level sensor as input span. When PR5343
is used with a potentiometer input, the PRelevel software contains the
following special functions for configuration:
[Calibration Password] is 4711. This password should be entered at program
start. The only parameters which can be changed without entering this
password are Input Low and High for the potentiometer input. The menu item
is located under Tools > Op tions. Please pay special attention to the text
in the 'Information' window during transmission. When the configuration
cannot be sent to the transmitter due to lack of password, the following
text will appear: 'Operation aborted.' 'Configuration NOT transmitted to the
device.'
The following description of configuration with potentiometer input is based on
figure 1. Please note that the PRelevel software only comes in an English-
language version. Therefore the menu texts are represented here as they are
seen on the screen. First choose the [Input] tab:
Figure 1, cross section of horizontal cylindrical tank
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[Electrical Calibration] Enter the range to be detected by the connected
potentiometer or let PRelevel measure the available range. The transmitter
must be connected to the communications interface before the values can be
measured. The values in figure 1 are Low = 3% og High = 97%.
[Placement Calibration] Enter the placement of the 'Electrical Calibration' Low
and High points of the level sensor in relation to the height of the tank. These
values are used for calculation of linearisation values and for calculation of 0
and 100% height.
The values in figure 1 are Low = 9% and High = 94%.
[Input] Enter the desired input span in relation to the height. When input Low
and High are selected as 0 and 100%, the input can never go below 9% and
above 94% due to the design and mounting of the level sensor. If the output
span is 4...20 mA, the output will only vary between 5.44...19.04 mA.
The values in figure 1 are Low = 0% and High = 100%.

Activation of embedded linearisations

The PRelevel software contains embedded linearisation functions for horizontal
cylindrical tanks and spherical tanks. The linearisation functions can be
activated as follows:
Custom input type: In order to gain access to a customer-defined linearisation,
the selection in the [General Type] input box must end with the text 'Custom'
and the [Calibration Password] 4711 must be entered.
Activation of linearisation: Choose the [Options] tab in the PRelevel 5343
window. If one of the embedded linearisations is to be used, the selection
in the 'Linearisation' window must be 'Polynomial.....(Relative)' in order to
retrieve the most accurate linearisation files. The files are retrieved by way
of the following menus: >Specify + select >File > Open in the main menu +
select >File name >Open in the file dialogue box.
User-defined linearisation: It is possible to enter specific linearisation tables in
the >Specify menu.
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