Hanna Instruments HI931, User Manual

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6-3
TITRA
TION MODE
6.1. RUNNING A TITRATION
Before beginning a titration, make sure that the following conditions are met:
• At least one pump is properly installed.
• A burette is inserted in the pump and filled with titrant.
• The aspiration tube is inserted in the titrant bottle and primed. The dispensing tube is over the titration beaker.
• The standard or sample has been carefully weighed/measured into the beaker.
• The electrode(s) and the temperature probe are submersed in the beaker.
• The desired method is selected and the parameters are set to the optimal values.
6.1.1. STARTING A TITRATION
To start a new analysis, press from the main screen.
When an analysis begins:
• The stirrer will turn on (if enabled).
• The pre-titration stir time starts, if enabled (see
Titration Methods section).
• After the pre-titration stir time is complete the pre-titration volume will be displayed, if enabled. (see Titration Methods
section).
• The titrator will start the analysis and continue to deliver titrant until the end point is detected or the titration is terminated.
6.1.2. SUSPENDING A TITRATION
While a titration is in progress, you can temporarily stop it by pressing . This will stop the dosing pump if it is running.
To continue the titration press .
6.1.3. VIEWING THE TITRATION CURVE
During a titration, the potentiometric curve and the derivative curve (equivalence point only) can be displayed on the Titration
Graph screen by pressing .
The potentiometric curve and the derivative curve are scaled to fit simultaneously inside the display.
When a titration end point is successfully detected, the volume is displayed on the graph and marked with an “x”.