Operating instructions

30 METTLER TOLEDO DL36
Maintenance and servicing
2. Anolyte
You should change the anolyte when
• the capacity limit is reached (see Section 8.1),
• the drift is too high (>10 µg/min) or the status "Stable" is no longer reached,
• its volume in the titration cell has reached 150 mL (upper marking on the titration cell); if the
anolyte is diluted too highly, the sensitivity is lowered and the titrations take longer.
– Siphon off the anolyte using the polyethylene bottle.
– Add 100 mL anolyte to the titration cell (up to the lower marking on the titration cell).
Notice: After the change, select Setup 1 and enter 0 for "A.Capacity". This sets the value of
the summed electric current (converted to mg H
2
O) of the anolyte to zero (see
Section 8.1).
11.7 Cleaning the detection electrode
– If the platinum pins of the electrode are contaminated, first clean with concentrated nitric
acid or carbon tetrachloride and then with methanol.
11.8 Cleaning and drying the inner burette
Place the DL36 in a fume hood! Never inhale the vapors of Karl Fischer
reagents and avoid skin contact! The reagents could damage your health.
1. Cleaning with methanol
– Switch off the DL36.
– Remove the inner burette from the titration cell and allow the catholyte to flow out.
– Degrease the joint surfaces with methanol.
– Rinse out the cathode of the inner burette two or three times with methanol.
– Add approx. 10 mL methanol and place in a beaker.
– Fill the beaker with methanol until the methanol level in the cathode is reached.
– Allow to stand for around 30 minutes, then empty the inner burette and dry it (see point
3).
WARNING