LimsPulse
KF titrator (volumetric) · Calibration procedure

Drift check

Confirms the conditioned titration cell is tight, by checking that the background drift is low and stable before use.

Photo of a KF titrator (volumetric)
Photo: Datamax, Public domain (cropped), via Wikimedia Commons
PURPOSE

Why this is checked

Moisture from the air, seals and reagent enters the cell continuously. The titrator corrects for it, but only if drift is low and steady. A high or unstable drift points to a leak or exhausted solvent or molecular sieve.

Frequency

Before every series of determinations and recorded with each result, as defined in your SOP.

Learn how the KF titrator (volumetric) works
YOU WILL NEED

Standards & tools

  • No external standard; the titrator's own drift measurement is used
BEFORE YOU START

Prerequisites

  • Fresh solvent in the cell
  • Active molecular sieve in the drying tubes
  • Septum and joints tight
PROCEDURE

Step by step

  1. 1Start conditioning and allow the titrator to dry the solvent.
  2. 2Record the drift at regular intervals (for example every 5 minutes).
  3. 3Confirm that the drift has fallen below the limit and has stopped changing.
  4. 4Record the final drift value in the logbook or software before running samples.
RECORD

Example observation table

Time after conditioning start (min)Drift (µg/min)
524
1013
158
208
CALCULATION

How to calculate the result

Drift correction (µg) = Drift (µg/min) × Titration time (min)
  1. Stable drift 8 µg/min, titration time 2.5 min
  2. Correction = 8 × 2.5 = 20 µg (0.020 mg) of water, subtracted automatically from the result
ACCEPTANCE CRITERIA

Pass if

  • Drift not more than 20 µg/min and stable (typical value for volumetric KF; use the limit in your SOP).
IF IT FAILS

What to do

  • Check and replace the septum and seals; regrease or reseat the joints.
  • Replace or regenerate the molecular sieve.
  • Exchange the solvent and recondition.
  • Do not start determinations until the drift meets the limit.
MORE

Other KF titrator (volumetric) calibrations

In LimsPulse · Calibration Management

LimsPulse schedules this calibration, records the result against limits, and blocks the instrument everywhere if it fails or goes overdue.

See how