Metrohm 796 Titroprocessor - Manual (Page 289)

13. Appendix
796 Titroprocessor, Instructions for use 283 283
Sensor test procedure:
• After the start of the test the sensor must be immersed in the first buffer
solution (pH 7) within five seconds.
• The stirrer is switched on automatically and the potential measured for
three minutes.
• The stirrer is then switched off and the potential measured for a further
minute.
• The buffer must then be changed (pH 4). By pressing [Next] the same
procedure is started again.
• The test data are displayed at the end of the sensor test.
ЪДДД Sensor test ДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДД¿
³ ³
³ Meas. input A1 ³
³ Temperature 25.0§C ³
³ ³
³ Buffer ** pH 7.0 ** ** pH 4.0 ** ³
³ time/min U/mV Drift/mV/Min U/mV Drift/mV/Min ³
³ ДДДДДДДДДД ДДДДДДДДДДДДДДДДДДДД ДДДДДДДДДДДДДДДДДДДД ³
³ 1 stirred 0.5 0.2 175.4 -0.4 ³
³ 2 stirred 0.4 0.0 175.3 -0.3 ³
³ 3 stirred 0.3 -0.2 175.2 -0.1 ³
³ 4 0.2 -0.2 175.1 -0.2 ³
³ ³
³ Response time 27.0 s OK 27.0 s OK ³
³ Stream.potent. 0.1 mV OK 0.1 mV OK ³
³ ДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДД ³
³ ³
³ Slope 0.986 OK ³
³ Zero point (mV) 0.3 mV OK ³
³ pH(as) 7.004 Summary: OK ³
АДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДДД QUIT ÄÙ
By pressing the [Extend. info] and [Full info] softkeys the test
results of a sensor can be shown again later. The test results of the previous
sensor tests are also shown.
13.5.3 System validation
GLP (Good Laboratory Practice) requires the regular checking of the re-
producibility and accuracy of analytical instruments by means of standard
operating procedures (SOP).
The Titroprocessor 796 should be validated as a complete, integrated titra-
tion system. A series of titrations (titer determinations are best) with primary
standards is recommended. The Titroprocessor can carry out the assess-
ment of the results and monitoring the validation intervals by itself.
In order to take the requirements of your specific applications into account,
the limiting values for the assessment of the reproducibility and accuracy of
the determinations can be individually set.
The validation can be carried out with any determination method which is
stored in the internal memory or on a data card. A simple modification of the
calculation formula will ensure the correct evaluation of the relevant data.