P-SOP0804-3262-E02
3/5
Standard Operating
Procedure
（
SOP
）
Automatic digital
Refractometer
RX-7000
α
(alpha)
3-2. Inspection by nD (refractive index)
The RX-
7000α
has the thermostatic function.
Measure distilled water by setting the targeted temperature to 10.0, 20.0, 30.0, 40.0,
50.0, 60.0, and 70
℃
respectively.
Be sure to perform zero adjustment with distilled water at each temperature. Then,
measure distilled water. Confirm that the measured value coincides with "each
temperature of the refractive index of distilled water".
Accuracy :
Under measurement temp. 10.0 to 30
℃
±
0.0002
Under measurement temp. 31.0 to 70
℃
±
0.0003
4. Calibration
1) Perform the calibration once a year.
2) Perform in accordance with the performance test method of operational qualification (OQ).
3) Record the data and other items in a performance test report, and have an operator
and approver’s signature. The manufacturer of the refractometer may also be
requested to perform calibration.
5. Maintenance
1)
When measurement is completed, be sure that nothing on the prism surface and
surrounding areas are completely wiped off with tissue paper moistened with water,
then wipe dry with tissue.
2)
When the body of the instrument is dirty, wipe it with dry tissue, cloth, etc.
3)
If the digital printer is used, the thermo sensitive roll paper is a consumable item.
4) Place the refractometer at a designated location. Keep it in a place of relative humidity
less than 75%
, if it is not to be used for a long period of time.
Temperature
Refractive index
10.0
℃
1.33369
20.0
℃
1.33299
30.0
℃
1.33194
40.0
℃
1.33061
50.0
℃
1.32904
60.0
℃
1.32725
70.0
℃
1.32533
When calibrating the RX-
7000α
at your company (end user), it is required to meet the
difficult conditions (maintenance and check for environmental conditions, examination
conditions and the accuracy of standard liquid, and the traceability of the jigs used) for
calibration.
In order to calibrate the RX-
7000α
, enormous expense and time may be spent.
When the matter of expense is taken into consideration, it may be more benefical to
request the manufacturer of the refractometer to carry out calibration.
* In that case, contact the company where the refractometer was purchased.
