Watson-Marlow PF6 - Manual (Page 16)

INSTRUCTION HANDBOOK
PF6
PF6 IH EN 74-105-022 v1.04.doc Version: 1.04 Page 16 of 30
5 Calibration
As the environment of the PF6 may vary from time to time and as tubes and products have small
tolerances, it is necessary to calibrate the drive when it is started. Recalibration is necessary during
production.
If the quantity has been entered as volume in ml, a measuring cylinder or a balance may be used as a
control and measuring unit. The balance will always be the more accurate, especially for small
quantities.
5.1 Initial volume calibration
If a volume has been entered in function 1, and a completed fill is measured with a balance, the
specific gravity of the liquid in question is to be entered in function 9.
(The parameters already entered may be used for a trial).
Prepare the balance by tarring the container and make sure that the tubes are completely filled, up to
and including the filling needle.
It is recommended to let the filler complete a few fills before the calibration is carried out.
Keep the tarred container below the filling needle and complete a single fill by pressing
<calib>+<GO> and PF6 will now ask for the completed volume showing the following display:
CALIB. WEIGHT : 0.0000__
F 1: VOLUME (ml) : 8.50
Fig. 11 – Calibration
In the prompt line, PF6 asks the weight, and the WEIGHT of the trial fill in question must be entered,
for example. 8.12: <8>+<.>+<1>+<2>+<ENT>
After calibration, complete a few fills and draw off a sample and check the volume.
If the volume is not at the level desired, carry out a re-calibration as described below.
Function 8 should now be reset, and the filling may be started by pressing <disp.>+<GO>.
5.2 Re-calibration
During production it may be necessary to recalibrate the volume dispensed by the filler to compensate
for changes in the environment e.g. the liquid level of the feed vessel will sink. This re-calibration may
be carried out without stopping the filling.
IT IS IMPORTANT TO USE THE SAME MEASURING METHOD FOR THE RECALIBRATION AS
USED FOR THE INITIAL CALIBRATION.
Draw off a filled sample and measure it. If the volume is not at the level desird, press <calib> + <Ent>
and then insert the measured value. Subsequently, let the production continue and draw off a sample
to check the volume again.
PF6 will now automatically adjust the subsequent fills.