Metrohm 709 IC Pump - Manual (Page 28)

3 Operation
709 IC Pump
20
3.2 Flow rate
The flow rate can be set in the range of 0.05 … 5.00 mL/min with the
pump drive switched on or off as follows:
1 Select "FLOW"
Press <SELECT> key 4 until the "FLOW" LED 10 lights up.
2 Set flow rate
Press < ↓ > key 5 or < ↑ > key 6 until the desired flow rate (in
mL/min) appears in display 1.
3 Store flow rate
Release < ↓ > key 5 or < ↑ > key 6: the value shown in display
1 at the time of release will be stored.
3.3 Flow correction
Since the difference between displayed and actual flow rate can be
maximum 3 % owing to unavoidable tolerances in the manufacture of
mechanical parts, there is a possibility to adjust the 709 IC Pump after
installation of a new pump head. For this, a correction factor of 0.9 … 1.1
can be entered in the 709 IC Pump.
The correction factor is determined by measurement of the actual flow
rate with the aid of a measuring cylinder:
Correction factor =
Displayed flow rate (in mL/min)
Measured flow rate (in mL/min)
In the entry of the correction factor, proceed as follows:
1 Select flow correction
Press <SELECT> key 4 for ca. 3 s until all LEDs (10...13) go out
and the correction factor appears in display 1.
2 Set flow correction
Press < ↓ > key 5 or < ↑ > key 6 until the desired flow correc-
tion appears in display 1.
3 Store flow correction
Release < ↓ > key 5 or < ↑ > key 6: the value shown in display
1 at the time of release will be stored.
4 Return to standby mode
Press <SELECT> key 4 briefly, the pump is again in the
standby mode.