K-Patents PR-23 - Manual (Page 186)

178 PR-23 instruction manual
13.1 Refractive index n
D
verification
Before starting the verifications procedures, make sure that you have a K-Patents
PR-23 sample holder at hand. Also check the condition of your standard refractive
index liquids. You’ll also need a cleaning solution (ethanol) to clean the sensor
prism and the sample holder.
The sample holder keeps the sample on the prism surface and also keeps the ambi-
ent light out. The K-Patents universal sample holder PR-1012 (Figure 13.1) can be
used with any K-Patents PR-23 sensor (in PR-23-M only the top part of the sample
holder is needed).
Figure 13.1 The universal sample holder PR-1012
The verification of the PR-23 sensor calibration is made using a set of standard
refractive index liquids with the nominal values at 25 °C:
− 1.330
− 1.370
− 1.420
− 1.470
− 1.520
The accuracy of the certified standard refractive index liquids is ±0.0002 and they
can be traced back to national standards: N.I.S.T Standards # 1823 and # 1823 II.
The repeatability of PR-23 sensor, i.e. the deviation from the latest n
D
calibration,
is within ±0.0002.
As the specified accuracy of PR-23 is ±0.0002, then the representative level is the
sum of the three accuracy specifications, that is ±0.0004.
K-Patents provides a set of standard R.I. liquids, PR-2300, containing these five
liquids. The set can be ordered directly from K-Patents or through your nearest
K-Patents representative.
13.2 Verification procedure
To start the verification process, select 1 VERIFICATION in the Main menu of your sen-
sor. The first verification display instructs you on the pre-verification procedure: