Watson-Marlow 620DuN and 620Du User Manual 52
20 MemoDoseEach time the pump is started by pressing START, it records the number of pump-
head revolutions which occur until STOP is pressed. The number of revolutions is
proportional to the volume of fluid which has been dispensed: the dose. The
MemoDose facility allows the user to repeat-dose a precise volume of fluid. To do so,
a quantity of fluid must be dispensed as the master dose which the MemoDose facil-
ity can repeat exactly or proportionately.
To dispense a master dose
In the manual mode main screen, set the appropriate pump speed and direc-
tion using the UP or DOWN keys and the DIRECTION (SHIFT, 1) key. An
example is shown here. A slower speed may make it easier for the user to
measure accurately - though it may not represent the duty condition.
Place a suitable measuring vessel under the pump delivery tube.
Press START. The pump runs and fluid is pumped into the vessel.
When the required volume of fluid has been dispensed, it is necessary to stop
the pump and display the MemoDose screen. This can be achieved in three
ways.
1 Press the STOP key twice within half a second. The pump stops and imme-
diately displays the MemoDose screen.
OR...
2 Press the STOP key once. The pump stops. (This may make it easier to
ensure that the quantity of fluid that has been dispensed is sufficiently pre-
cise.) Then press the STOP key twice within half a second. The pump dis-
plays the MemoDose screen.
OR ...
3 Press the STOP key. The pump stops. Press the MENU (SHIFT, 7) key. Use
the UP or DOWN keys to select MemoDose. Press ENTER to confirm. The
pump displays the MemoDose screen.
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