Characteristics Test; Analog Output Characteristics; Linear - Hach ORBISPHERE G1100 User Manual

Inputs/Outputs Menu

8.4.5 Characteristics test

8.5 Analog output characteristics

There are three types of output

Linear

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Tri-linear
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None
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8.5.1 Linear
The "Linear" output is the default setting for the analog output. It is illustrated in
(4-20 mA output is shown, 0-20 mA or 0-5 V settings are similar).
The goal of this setting is to use all the points available on the slope from 4 mA to 20 mA to
show the range of measurements that are usual in the measured process. Setting the output
this way allows for the highest signal resolution for the actual conditions.
The downside is that any measures below the set range will have the same analog signal
locked at 4 mA. Similarly, any measure over the set range will have the same analog signal
locked at 20 mA. Settings must made in balancing these aspects.
Settings
For the output, set ML and MH in the current measuring unit (e.g. °C for a temperature output).
When a compound unit is selected the smallest unit will be used (e.g. ppb for a "ppm-ppb"
compound unit).
These points should be set keeping in balance the following conditions
The smaller is Range 1, the better is the analog signal resolution within the expected range
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of measure.
In Range 0 the analog output only shows that measurement is below the ML value. Similarly
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in Range 2 the analog output only shows that measurement is over the MH value.
70
This is a test for the correct operation of the peripherals
connected to each analog output, by verifying that the PLC
computes the correct value.
The analog output will send the current corresponding to the
value entered in the text boxes.
Type in a test value for each analog output, and check for
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the related action on the peripheral.
Figure 37 "Linear" characteristics diagram
Figure 37 below
(Figure 37 above):