Swan Analytical Instruments A-85.119.010, Manual

Page: 57 / 131

6 - Maintenance - Repair
Calibration
6.5 Calibration
6.5.1 General notes on
calibration
Calibration
sequence
As the DIS measurement depends on the pH value, always
calibrate pH (if optional pH sensor installed) first, then DIS.
Calibration
frequency
See 6.
2 “Maintenance schedule”,
34 .
Run-in
periods
Operate for 24 h before calibrating the system after
– initial instrument installation,
– cleaning the Trides sensor and/or reference electrode,
– replacing the Trides sensor and/or reference electrode.
Operate for 5 days before calibrating the system if
– measuring in the low level range (< 0.1 ppm).
Process pH Manual measurement of pH value which is then written to the
instrument (one point calibration).
Š
Upon initial instrument installation, operate for 1 h
before measuring the pH value.
Š
Use reliable, high quality pH meter and pH sensor such
as the CHEMATEST 25 from SWAN.
Standard pH Extensive two point calibration by means of two buffer solutions
such as the pH7/pH9 calibration set.
Š
If done upon initial instrument installation, operate for 1
h before calibration.
Zero Trides Determination of the zero DIS value (0.00 ppm).
Calibrate Zero Trides, by observing the Run-in periods , after
Š
cleaning the Trides sensor,
Š
replacing the Trides sensor.
Process
Trides
DIS measurement by means of DPD method, obtained value is
written to the instrument.
Š
Use reliable, high quality photometer such as the
CHEMATEST 25 from SWAN.
Cal. history See 5.1.
2 “Menu Sensors 2.2”,
30 .
AMI Trides Operator’s Manual, A-96.250.101
49