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Hi, I’m Jennifer Caban.

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Today I’m going to
show you how to adjust

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user factors on your
Vanta XRF analyzer.

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User factors allow you to adjust

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the factory default calibration

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to account for site
specific matrix effects.

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You can do this using
certified reference materials,

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your own internal standards,

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or samples that have been
analyzed in a lab.

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In today’s example,
silicone is reading

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a bit low on the Vanta
on geological standards

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compared to the laboratory assays.

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It’s not uncommon to have to adjust

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the factory default calibration.

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When you do this you want

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to use at least three standards,

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but the more standards you use,

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the more robust the calibration.

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The first step is to test
each of your standards

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with the Vanta XRF analyzer.

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Testing time can be either the same

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as your standard testing time

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or, to minimize statistical variation

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you can test for up to
two to three times

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longer than standard testing times.

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This standard is assayed
at about 26.0% silicone.

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We’ll see what result
we’ll get with the Vanta.

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The test is complete
and with the Vanta

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I’m reading about 22.8% silicone.

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I’m going to export that result

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along with the results
on my other standards

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and compare that in an X/Y plot

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to the laboratory assays.

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I’ve done that here in
an Excel® spreadsheet.

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I have the Vanta XRF results
on the X axis

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and the laboratory
assays on the Y axis.

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I’ve also enabled the
display equation feature

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on the graph so that I have a slope

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and a Y intercept of my line.

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These are the values that
I’m then going to import

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into the user factors menu
on the Vanta.

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Going back to the Vanta,

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I’m going to swipe down
on the right hand side

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and select the User Factors option.

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I’m going to create a model

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which I’ll call Si for silicone.

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I’m then going to take the slope

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and the Y intercept from
the line I plotted in Excel®

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and input those in as
the factor and the offset.

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The factor was one point
one one nine nine.

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For the offset,
I plotted this in Excel®

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as a percent but
the Vanta is calling for it

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as parts per million.

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So I need to convert
that percent value

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to parts per million
in order to input it.

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The converted value is
seventeen thousand twenty seven.

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And that’s it, I’ve now created

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the user factor model on my Vanta.

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I can now go back and test

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my standard with the new model.

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Recall that the assayed
value for this standard

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is about 26.0% silicone and when

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I first tested the sample I was
getting about 22.8% silicone.

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We’ll see what we get with the

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new user factor model enabled.

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With the new model I’m
getting about 26.9% silicone

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which is significantly closer to the

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assayed value of 26.0%.

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And that’s it,

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that’s how you create user factors

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on the Vanta XRF analyzer.

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Thanks for watching!