Quadbeam Technologies MXD70 Series, Set Up And Operating Manual, Page: 16 / 52

Channel Setup
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MXD70 Suspended Solids / Turbidity
Setup and Operating Guide
Channel Setu
p
Linearisation Curve Setup
With many solutions the rate of infra-red absorption is non linear as the solids concentration increases.
The purpose of this function is to take the probe signal values from several samples and convert this
non-linearity to a straight line output. In many cases this is the only calibration procedure required.
It is recommended that the user should first prepare or obtain from the process a sample, which is as
close as possible to the maximum range of suspended solids for which the instrument is to be
configured. This will be your 100% point. For a two point linearisation curve the lower point is usually
water. Where you want to enter more than two points, dilute your process sample to correspond with,
for example, 25%, 50% and 75%. Up to10 points can be entered, with the more points that are used
the more precise the conversion will be.
The MXD70 provides two methods, automatic and manual, for entering the curve data into the
instrument.
Automatic Curve Entry
Automatic Curve Entry allows the user to set the number of points used in the curve. Then for each
point define the engineering value and equate it to a live reading taken from the sensor placed in the
desired sample. Note that the points can be sampled in any order as they are sorted into ascending
probe signal values from within the software.
Number Of Points
Set the number of points used to define the
linearisation curve. The instrument will ignore any
points whose equivalent probe signal value is set to
zero.
The curve can use between 2 – 10 points.

/

– Select Option
EXIT – Return to Channel Setup
– Enter Option
Setup All Points
Enter here to start the automatic linearisation routine
and setup all curve points.

/

– Select Option
EXIT
– Return to Channel Setup
AUTO
– Enter Routine